Physical Address

304 North Cardinal St.
Dorchester Center, MA 02124

P


Paclitaxel — (Onxol; Taxol)

International Brand Names

Anzatax (Australia, Brazil, China, Hong Kong, Malaysia, Philippines, Singapore, Taiwan, Thailand); Asotax (Argentina, Mexico); Biotax (Israel); Bristaxol (Mexico); Britaxol (Chile); Formoxol (Malaysia); Genexol (Korea, Singapore); Ifaxol (Mexico); Intaxel (India, Thailand); Medixel (Israel); Mitotax (Malaysia); Pacxel (Korea); Padexol (Korea); Parexel (Colombia, Ecuador, Paraguay); Paxus (Indonesia); Praxel (Chile, Mexico); Taxocris (Uruguay); Taxol (Argentina, Canada, China, Ecuador, Germany, Hong Kong, Indonesia, Israel, Korea, Malaysia, New Zealand, Philippines, South Africa, Thailand); Taycovit (Peru)

Drug Class Antineoplastics; Antimitotics
Indications Malignancy, metastatic ovarian or breast cancer, lung (non–small cell) cancer, and HIV-related Kaposi’s sarcoma
Mechanism Inhibits mitosis by promoting assembly and stabilization of microtubules
Dosage With Qualifiers Metastatic ovarian or breast cancer, lung (non–small cell) cancer, and HIV-related Kaposi’s sarcoma—dosing regimens vary

  • Contraindications —hypersensitivity to drug or class, hypersensitivity to castor oil , neutropenia

  • Caution —radiation therapy, pregnancy

Maternal Considerations Ovarian cancer is the fifth most diagnosed cancer during pregnancy. A taxane plus a platinum derivative is used to treat ovarian cancer in nonpregnant women. Paclitaxel is a natural product have been usually combined with cisplatin as first-line therapy. Numerous women have given paclitaxel during pregnancy with successful outcomes. Only one team has studied the pharmacokinetics of paclitaxel (175 mg/m 2 IV over 3 h) during pregnancy. The C max and AUC were decreased compared to nonpregnant patients. The estimated clearance, t/2, and volume of distribution were each within the ranges previously reported for nonpregnant patients.
Side effects include alopecia, neutropenia, leukopenia, thrombocytopenia, N/V, diarrhea, anemia, arthralgia, myalgia, peripheral neuropathy, infection, elevated LFTs, and injection site reactions.
Fetal Considerations There are no well-controlled studies in human fetuses. Paclitaxel crossed the placenta in the ex vivo human placenta perfusion model. However, placental transfer was low and altered by albumin concentration. Several case reports note the development of oligohydramnios during paclitaxel therapy. The risks of structural malformation and miscarriage increase during the first trimester. However, exposure during the second and third trimesters does not appear to increase fetal mortality, IUGR, or IUFD rates significantly. Rodent studies reveal embryotoxicity and IUGR, but no teratogenicity.
Breastfeeding Safety Paclitaxel is excreted into human breast milk. The relative infant dose is 14%–23%. It should be considered potentially hazardous.
Drug Interactions Catalyzed by CYP2C8 and CYP3A4. In the absence of formal clinical drug interaction studies, caution should be exercised when administering paclitaxel or paclitaxel protein-bound particles for injectable suspension with known substrates or inhibitors of CYP2C8 and CYP3A4. Potential interactions between paclitaxel, a substrate of CYP3A4, and protease inhibitors (e.g., indinavir, nelfinavir, ritonavir, saquinavir ), which are substrates and/or inhibitors of CYP3A4, have not been evaluated in clinical trials.
In a phase I trial, myelosuppression was more profound when paclitaxel was given after cisplatin than with the alternate sequence (i.e., paclitaxel before cisplatin ). Pharmacokinetics data from these patients demonstrated a one-third decrease in paclitaxel clearance.
Some reports suggest that plasma levels of doxorubicin (and its active metabolite doxorubicinol) may be increased when paclitaxel and doxorubicin are used together.
References Berveiller P, Vinot C, Mir O, et al. Am J Obstet Gynecol 2012; 207:514.e1-514.e7.
Fruscio R, de Haan J, Van Calsteren K, et al. Best Pract Res Clin Obstet Gynaecol 2017; 41:108-17.
Griffin SJ, Milla M, Baker TE, et al. J Hum Lact 2012; 28:457-9.
Kai S, Kohmura H, Hiraiwa E, et al. J Toxicol Sci 1994; 19(Suppl 1):69-111.
Lycette JL, Dul CL, Munar M, et al. Clin Breast Cancer 2006; 7:342-4.
Mir O, Berveiller P, Ropert S, et al. Ann Oncol 2008; 19:607-13.
Sood AK, Shahin MS, Sorosky JI. Gynecol Oncol 2001; 83:599-600.
Zheng X, Zhu Y, Zhao Y, et al. Int J Clin Pharmacol Ther 2017; 55:753-60.
Summary Pregnancy Category: D
Lactation Category: NS (probably)

  • Paclitaxel should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

  • Initiate therapy after organogenesis when possible.

Pamidronate — (Aredia)

International Brand Names

Aminomux (Argentina, Paraguay, Uruguay, Venezuela); Aredia (Brazil, Canada, Chile, China, Colombia, Hong Kong, Indonesia, Japan, Mexico, Peru, Philippines, Taiwan, Thailand); Aredronet (India); Ostepam (France); Pamisol (Malaysia, Singapore); Panolin (Korea); Panorin (Korea)

Drug Class Bisphosphonates
Indications Paget’s disease, malignant hypercalcemia, osteolytic lesions
Mechanism Inhibits osteoclast bone resorption
Dosage With Qualifiers Paget’s disease—30 mg IV infused over 4 h qd × 3 d
Hypercalcemia secondary to malignancy—60–90 mg IV infused over 24 h × 1; wait 7 d between treatments
Osteolytic lesions—90 mg IV infused over 4 h qmo

  • Contraindications —hypersensitivity to drug or class

  • Caution —renal dysfunction

Maternal Considerations There are no adequate reports or well-controlled studies of pamidronate in pregnant women. The published experience consists of several case reports. In one, pamidronate was used in the third trimester to treat hypercalcemia secondary to metastatic breast carcinoma. There was no apparent adverse effect. In another, a woman with metastatic breast cancer was treated at 28 w after unsuccessful chemotherapy, deteriorating renal function, frequent contractions, and a calcium level of 17.6 mg/dL. Pamidronate dramatically decreased both the calcium levels and the frequency of uterine contractions. In six other instances, women with either polyostotic fibrous dysplasia or osteogenesis imperfecta were treated before conception and throughout pregnancy without any apparent adverse maternal or fetal effects. In animal studies, pamidronate inhibits bone resorption at the recommended dose for hypercalcemia, apparently without inhibiting bone formation and mineralization.
Side effects include N/V, dyspepsia, seizures, hypertension, thrombocytopenia, leukopenia, hypokalemia, hypocalcemia, hypomagnesemia, hypophosphatemia, tachycardia, anorexia, fever, confusion, psychosis, pain, and fatigue.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether pamidronate crosses the human placenta. The limited human experience is reassuring. Indeed, pamidronate may represent an ameliorating fetal therapy for congenital osteogenesis imperfecta if there is placental transport. Rodent studies revealed maternal toxicity, presumably associated with hypocalcemia, and fetal skeletal retardation, but no evidence of teratogenicity. The delayed skeletal formation suggests pamidronate crosses the rodent placenta.
Breastfeeding Safety There are no reports or well-controlled studies in nursing women. In a single case report, pamidronate was not found in human breast milk after a single IV dose. Women with hereditary hyperphosphatasia, a rare bone disorder characterized by increased bone turnover, may develop symptomatic hypercalcemia during lactation.
Drug Interactions Caution is recommended when administering with other potentially nephrotoxic drugs.
References Chan B, Zacharin M. J Clin Endocrinol Metab 2006; 91:2017-20.
Culbert EC, Schfirin BS. Obstet Gynecol 2006; 108:789-91.
Graepel P, Bentley P, Fritz H, et al. Arzneimittelforschung 1992; 42:654-7.
Illidge TM, Hussey M, Godden CW. Clin Oncol (R Coll Radiol) 1996; 8:257-8.
Munns CF, Rauch F, Ward L, Glorieux FH. J Bone Miner Res 2004; 19:1742-5.
Siminoski K, Fitzgerald AA, Flesch G, Gross MS. J Bone Miner Res 2000; 15:2052-5.
Stathopoulos IP, Liakou CG, Katsalira A, et al. Hormones (Athens) 2011; 10:280-91.
Summary Pregnancy Category: C
Lactation Category: S

  • Pamidronate should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

Pancrelipase — (Amylase; Amylase Lipase Protease; Cotazym-S; Creon; Creon 5; Donnazyme; Encron 10; Entolase; Enzymase 16; Festalan; Ilozyme; Ku-Zyme HP; Lipase; Panase; Pancote; Pancrease; Pancreatic Enzyme; Pancreatin 10; Pancrelipase 10000; Pancrelipase Mt 16; Pancrelipase Mt-16; Pancron 10; Panokase; Promylin; Protease; Protilase; Protilase Mt 16; Ultrase; Ultrase Mt; Vio-Moore; Zymase)

International Brand Names

Combizym (New Zealand); Combizym Compositum (New Zealand); Cotazym (Canada); Cotazym-65 B (Canada); Cotazym ECS (New Zealand); Cotazym-S (Australia); Cotazym-S Forte (Australia); Creon (Canada); Krebsilasi (Italy); Pancrease (Belgium, Denmark, Finland, Israel, Italy, Netherlands, Norway, Spain, Sweden); Pancrease HL (England); Pancrease MT (Canada); Pancrease MT 4 (Canada); Pancrease MT 10 (Canada); Pancrease MT 16 (Canada); Pancrex (Italy); Pankrease (South Africa); Panzytrat (New Zealand); Prolipase (Austria, Poland, Switzerland); Ultrase (Canada); Ultrase MT (Canada); Vitazyme (Malaysia)

Drug Class Digestive enzymes; Gastrointestinals
Indications Pancreatic insufficiency
Mechanism Disintegrates into trypsin, amylase, and lipase
Dosage With Qualifiers Pancreatic insufficiency—1–3 tabs PO swallowed quickly with meals depending on preparation
NOTE: Do not cut, crush, or chew.

  • Contraindications —hypersensitivity to drug or class, allergy to pork, acute pancreatitis

  • Caution —unknown

Maternal Considerations The enzymes in pancrelipase act locally in the GI tract, where either they may be digested or their constituents partially absorbed and subsequently excreted in the urine. Undigested enzymes are excreted in the feces. There is no published experience in pregnancy, though it is used commonly for the treatment of cystic fibrosis.
Side effects include N/V, diarrhea, stomatitis, oral ulceration, rash, urticaria, hyperuricemia, and perianal irritation.
Fetal Considerations There are no adequate reports or well-controlled studies of pancrelipase in human fetuses. The enzymes are not absorbed in a functional format and pose no risk to the fetus. Rodent studies are reassuring, revealing no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically.
Breastfeeding Safety There is no published experience with pancrelipase in nursing women. However, the enzymes are not absorbed systemically and are unlikely to enter human breast milk.
Drug Interactions Antacids containing calcium carbonate and magnesium hydroxide should not be taken concurrently, as the combination may precipitate glycine-conjugated bile acids and form calcium and magnesium fatty acid soaps, causing a decrease in fat absorption and thus an increase in steatorrhea.
References There are no current relevant references.
Summary Pregnancy Category: B
Lactation Category: S

  • Pancrelipase should be used during pregnancy and lactation if the benefit justifies the potential perinatal risk.

Pancuronium — (Pavulon)

International Brand Names

Alpax (Israel); Bromurex (Colombia, Mexico); Curon-B (South Africa); Panconium (India); Pancuron (Paraguay); Pancuronio (Colombia); Pavulon (Argentina, Australia, Brazil, Canada, Chile, France, India, Japan, Korea, South Africa, Sweden, Venezuela)

Drug Class Neuromuscular blockers, nondepolarizing
Indications Anesthesia, paralysis
Mechanism Blocks acetylcholine motor end plate receptors
Dosage With Qualifiers Paralysis—0.04–0.1 mg/kg IV
Paralysis, fetal—0.3 mg/kg (maximum 0.6mg) fetal IM or IV into the umbilical vein

  • Contraindications —hypersensitivity to drug or class

  • Caution —hypovolemia, hepatic dysfunction

Maternal Considerations There are no adequate reports or well-controlled studies of pancuronium in pregnant women. However, there is a long clinical experience for cesarean delivery. Pancuronium is approximately one-third less potent than vecuronium, though its duration is longer at equipotent doses. As compared to vecuronium, pancuronium is also vagolytic with accompanying tachycardia—desirable for fetal transfusion. Magnesium sulfate enhances the neuromuscular blockade, and reversal may be incomplete. Anticholinesterase agents such as edrophonium, neostigmine, and pyridostigmine will reverse neuromuscular blockade.
Side effects include arrhythmia, hypertension, tachycardia, rash, increased salivation, and pruritus.
Fetal Considerations There are no adequate reports or well-controlled studies of pancuronium in human fetuses. There is minimal transport across the human placenta. Pancuronium is often used for fetal paralysis to facilitate intrauterine procedures. Because it increases HR, pancuronium blunts the normal decline in cardiac output after fetal intravascular transfusion. Fetal paralysis modestly reduces oxygen consumption.
Breastfeeding Safety There is no published experience in nursing women. It is unknown whether pancuronium enters human breast milk. However, it is unlikely a significant amount would enter the breast milk given once for the described indications.
Drug Interactions Succinylcholine may enhance the neuromuscular blocking effect and increase its duration of action. If succinylcholine is used first, the pancuronium should be delayed until the patient starts to recover from the succinylcholine -induced neuromuscular blockade. If a small dose of pancuronium is given at least 3 min prior to the administration of succinylcholine, in order to reduce the incidence and intensity of succinylcholine -induced fasiculations, it may cause respiratory depression in some patients. Other nondepolarizing neuromuscular blocking agents (e.g., atracurium, d - tubocurarine, gallamine, metocurine, vecuronium ) behave in a fashion clinically similar to pancuronium . The combinations of pancuronium -metocurine and pancuronium– d - tubocurarine are significantly more potent than the additive effects of each of the individual drugs given alone; however, the duration of blockade of these combinations is not prolonged.
Use of volatile inhalational anesthetics (e.g., enflurane , isoflurane , halothane ) will enhance neuromuscular blockade. Potentiation is most prominent with enflurane and isoflurane.
Clinical experience and animal experiments suggest caution when giving pancuronium to patients receiving chronic TCA therapy who are anesthetized with halothane, as severe ventricular arrhythmias may result from this combination.
Parenteral/intraperitoneal administration of high doses of certain antibiotics (e.g., aminoglycosides such as dihydrostreptomycin, gentamicin, kanamycin, neomycin, and streptomycin; tetracyclines; bacitracin; polymyxin B; colistin; and colistimethate ) may intensify or produce a neuromuscular block on their own. If these or other newly introduced antibiotics are used preoperatively or in conjunction with pancuronium, unexpected prolongation of neuromuscular block should be considered a possibility.
Use of quinidine during recovery from use of other muscle relaxants may trigger recurrent paralysis.
Electrolyte imbalance may alter neuromuscular blockade. Depending on the nature of the imbalance, either enhancement or inhibition can be expected. Magnesium sulfate, administered for the management of preeclampsia/eclampsia, may enhance the neuromuscular blockade.
References Dailey PA, Fisher DM, Shnider SM, et al. Anesthesiology 1984; 60:569-74.
Higashi T, Kamo N, Naitou H, Tada K. Masui 1996; 45:96-8.
Wilkening RB, Boyle DW, Meschia G. Am J Physiol 1989; 257:H734-8.
Summary Pregnancy Category: C
Lactation Category: U

  • Pancuronium should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

Pantoprazole — (Protonix; Somac)

International Brand Names

Branzol (Uruguay); Controloc (Bulgaria, Egypt, Hungary, Iran, Israel, Jordan, Malaysia, Poland, Singapore, Thailand); Eupantol (France); Inipomp (France); Pantecta (Costa Rica, Dominican Republic, El Salvador, Guatemala, Honduras, Italy, Nicaragua, Panama); Pantodac (India); Pantodar (Israel); Pantoloc (Austria, Canada, China, Denmark, Hong Kong, Korea, Philippines, Taiwan); Pantop (Argentina); Pantozol (Germany, India, Indonesia, Israel, Mexico, Netherlands); Pepticus (Paraguay); Protium (England, Ireland); Rifun 40 (Germany); Ulcepraz (Philippines); Ziprol (Brazil); Zoltum (Peru); Zurcal (Austria, Chile, Colombia, Ecuador, Mexico, Peru); Zurcale (Belgium); Zurcazol (Greece)

Drug Class Antiulcer; Gastrointestinals; Proton pump inhibitors
Indications Erosive esophagitis, hypersecretory conditions
Mechanism Inhibits gastric parietal cell hydrogen-potassium ATPase
Dosage With Qualifiers Erosive esophagitis—40 mg PO qd or bid × 8 w; may repeat course followed by maintenance of 40 mg/d
Hypersecretory conditions—begin 40 mg PO bid; max 240 mg qd
NOTE: Do not crush, cut, or chew tablet.

  • Contraindications —hypersensitivity to drug or class

  • Caution —long-term use

Maternal Considerations Pantoprazole seems effective for the approved indications and is available without prescription. Proton pump inhibitors appear to lower at least transiently several protein markers of preeclampsia including sFlt-1, endoglin, and endothelin-1 level. In vitro , it modestly decreases the contractility of myometrial strips obtained from pregnant women at delivery.
Side effects include headache, diarrhea, pancreatitis, blood dyscrasias, hepatic dysfunction, toxic epidermal necrolysis, and erythema multiforme.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether pantoprazole crosses the human placenta. Fetal exposure to either H 2 blockers or proton pump inhibitors appears to modestly increase the risk of childhood asthma. The risk increases with the duration of exposure. Rodent studies are reassuring, revealing no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically.
Breastfeeding Safety There are no well-controlled studies in nursing women. The relative infant dose is estimated to be about 1%. In one study, pantoprazole was present in human breast milk only at 2 and 4 h postdose, and the levels achieved were unlikely to have any effect on the fetus. Pantoprazole is excreted into rodent milk.
Drug Interactions Metabolized primarily through CYP2C19 and CYP3A4 isozymes and subsequently undergoes phase II conjugation. No dose adjustments will be needed with the use of the following: amoxicillin, antipyrine, caffeine, carbamazepine, cisapride, clarithromycin, diazepam (and its active metabolite, desmethyldiazepam), diclofenac, digoxin, ethanol, glyburide, levonorgestrel/ethinyl estradiol, metoprolol, metronidazole, midazolam, naproxen, nifedipine, phenytoin, piroxicam, or theophylline.
There are postmarketing reports of increased INR and PT in patients receiving both proton pump inhibitors, including pantoprazole, and coumarin. Increases in INR and PT may lead to abnormal bleeding and even death. Patients should be monitored closely.
May interfere with absorption of drugs for which gastric pH is an important determinant of bioavailability (e.g., ampicillin esters, iron salts, ketoconazole ), as pantoprazole profoundly inhibits gastric acid secretion.
References Danser AHJ. Hypertension 2017; 70:594-600.
Diav-Citrin O, Arnon J, Shechtman S, et al. Aliment Pharmacol Ther 2005; 21:269-75.
Plante L, Ferron GM, Unruh M, et al. Reprod Med 2004; 49:825-7.
Saleh L, Samantar R, Garrelds IM, et al. Eur J Pharm Sci 2014; 52:125-31.
Yitshak-Sade M, Gorodischer R, Aviram M, Novack L. J Clin Pharmacol 2016; 56:116-23.
Summary Pregnancy Category: B
Lactation Category: S (probably)

  • Pantoprazole should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

  • There are alternative agents for which there is more experience regarding use during pregnancy and lactation.

Pantothenic acid — (Vilantae)

International Brand Names

None identified.

Drug Class Vitamins/minerals
Indications Supplementation
Mechanism Unknown
Dosage With Qualifiers Supplementation—RDA not established, but 6 mg daily is typically suggested

  • Contraindications —hypersensitivity to drug or class

  • Caution —unknown

Maternal Considerations Pantothenic acid (aka vitamin B 5 ) is a water-soluble B vitamin. There are no adequate reports or well-controlled studies of pantothenic acid in pregnant women. Its level may decline modestly during pregnancy.
Side effects are not reported.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. Pantothenic acid is actively transported across the placenta. Epidemiologically, maternal intake of pantothenic acid correlates with birth weight, birth length, and head circumference. However, it is not presently known whether maternal supplementation increases the fetal concentration. Supplementation reduces the incidence of NTDs in mice treated with valproate.
Breastfeeding Safety There are no adequate reports or well-controlled studies in nursing women. Pantothenic acid enters human breast milk, and the concentration in term milk correlates with maternal serum, dietary intake, and urinary excretion. Maternal serum levels may decline modestly during lactation without supplementation.
Drug Interactions No clinically relevant interactions identified.
References Dawson JE, Raymond AM, Winn LM. Toxicol Appl Pharmacol 2006; 211:124-32.
Lagiou P, Mucci L, Tamimi R, et al. Eur J Nutr 2005; 44:52-9.
Sato M, Shirota M, Nagao T. Teratology 1995; 52:143-8.
Song WO, Chan GM, Wyse BW, Hansen RG. Am J Clin Nutr 1984; 40:317-24.
Song WO, Wyse BW, Hansen RG. J Am Diet Assoc 1985; 85:192-8.
Summary Pregnancy Category: A
Lactation Category: S

  • Pantothenic acid is a common component of prenatal vitamins.

Paregoric

International Brand Names

None identified.

Drug Class Antidiarrheals; Narcotics
Indications Diarrhea
Mechanism Binds opioid receptors
Dosage With Qualifiers Diarrhea—5–10 mL qd to qid prn loose stools

  • Contraindications —hypersensitivity to drug or class, hypersensitivity to morphine, diarrhea secondary to toxic metal poisoning

  • Caution —head injury, abdominal pain of unknown origin

Maternal Considerations Paregoric is a mixture of opium powder (anhydrous morphine, 0.4 mg/mL) and ethanol. Other ingredients include benzoic acid, camphor, and anise oil. Its main actions are to increase intestinal muscular tone and to inhibit normal peristalsis. Paregoric’s principal medicinal use is to control fulminant diarrhea. It is also an antitussive. Paregoric is sometimes confused with laudanum, because their chemical names are similar: camphorated tincture of opium ( paregoric ) vs. tincture of opium ( laudanum ). However, laudanum contains 10 mg/mL of opium, 25 × more than paregoric. Confusion between the two drugs has led to overdose and deaths. The term paregoric should always be used instead of camphorated opium tincture, as the latter may be confused with laudanum . There are no adequate reports or well-controlled studies of paregoric in pregnant women. It does not delay or inhibit preterm labor. See Morphine.
Side effects include hypotension, convulsions, and SVT.
Fetal Considerations There are no adequate reports or well-controlled studies of paregoric in human fetuses. Morphine crosses the placenta and enters the fetal circulation. Rodent teratogenicity studies have not been conducted, though the large clinical experience is reassuring. Paregoric is used postnatally to treat neonatal withdrawal. See Morphine.
Breastfeeding Safety There are no adequate reports or well-controlled studies of paregoric in nursing women. Morphine is present in breast milk (see Morphine ).
Drug Interactions See Morphine.
The patient should be advised that morphine in combination with other narcotic analgesics, general anesthetics, phenothiazines, tranquilizers, sedative-hypnotics, or other CNS depressants (including ethanol ) has additive depressant effects and, when combined, the dose of one or both agents should be reduced.
References Levy M, Spino M. Pharmacotherapy 1993; 13:202-11.
Summary Pregnancy Category: C
Lactation Category: S

  • Paregoric should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

  • There are alternative agents for which there is more experience regarding use during pregnancy and lactation.

Paricalcitol — (Zemplar)

International Brand Names

None identified.

Drug Class Calcium metabolism agents
Indications Hyperparathyroidism, typically secondary to dialysis
Mechanism Stimulates intestinal calcium and phosphorus absorption, bone mineralization; reduces PTH
Dosage With Qualifiers Secondary hyperparathyroidism—0.04–0.1 mcg/kg IV 3 ×/w; max 0.24 mcg/kg

  • Contraindications —hypersensitivity to drug or class, vitamin D toxicity, hypercalcemia

  • Caution —unknown

Maternal Considerations Paricalcitol is a synthetic vitamin D analog. There is no published experience in pregnancy.
Side effects include hypercalcemia, N/V, fever, chills, edema, sepsis, light-headedness, pneumonia, GI bleeding, palpitations, and dry mouth.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether paricalcitol crosses the human placenta. The results of rodent studies are mixed. Sequelae may reflect hypocalcemia rather than the drug.
Breastfeeding Safety There is no published experience during lactation. It is unknown whether paricalcitol enters human breast milk. It is secreted into milk of lactating rats.
Drug Interactions Partially metabolized by CYP3A, and ketoconazole is known to be a strong CYP3A inhibitor. A multiple-dose drug-drug interaction study revealed ketoconazole roughly doubled the paricalcitol AUC. Care should be taken when using ketoconazole and other strong CYP3A inhibitors (e.g., atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, voriconazole ). A dose adjustment of paricalcitol may be required.
Drugs that impair intestinal absorption of fat-soluble vitamins, such as cholestyramine, may interfere with the absorption of paricalcitol.
Digitalis toxicity is potentiated by hypercalcemia of any cause, so caution should be applied when digitalis compounds are prescribed with paricalcitol.
References There are no current relevant references.
Summary Pregnancy Category: C
Lactation Category: S (likely)

  • Paricalcitol should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

Paromomycin — (Humatin)

International Brand Names

Gabbroral (Belgium, Bulgaria, Indonesia, Italy, South Africa); Humagel (France); Humatin (Austria, Bulgaria, Canada, Ecuador, Germany, Italy, Spain, Switzerland)

Drug Class Antibiotics; Aminoglycosides; Antiprotozoals
Indications Intestinal amebiasis, management of hepatic coma
Mechanism Bactericidal—inhibits protein synthesis by binding the bacterial 30S ribosomal subunit
Dosage With Qualifiers Intestinal amebiasis—25–35 mg/kg/d PO with meals × 5–10 d
Management (adjunctive) of hepatic coma—4 g PO tid × 5–6 d

  • Contraindications —hypersensitivity to drug or class, intestinal obstruction

  • Caution —bowel ulcerations

Maternal Considerations Paromomycin closely parallels neomycin . It is poorly absorbed orally—nearly 100% is recoverable from the stool. There are no adequate reports or well-controlled studies in pregnant women. A single case report documents the successful treatment of giardiasis.
Side effects include N/V, abdominal cramps, and diarrhea.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether paromomycin crosses the human placenta. However, it is unlikely the maternal systemic concentration will reach a clinically relevant level.
Breastfeeding Safety There are no adequate reports or well-controlled studies in nursing women. It is unknown whether paromomycin enters human breast milk. However, it is generally considered compatible with breastfeeding because of the poor oral absorption.
Drug Interactions No clinically relevant interactions identified.
References Kreutner AK, Del Bene VE, Amstey MS. Am J Obstet Gynecol 1981; 140:895-901.
Summary Pregnancy Category: C
Lactation Category: S (probably)

  • Paromomycin should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

Paroxetine — (Paxil)

International Brand Names

Aropax 20 (Argentina, Belgium, Brazil, Mexico, Paraguay, South Africa, Uruguay); Aroxat (Chile); Deroxat (France); Divarius (France); Paroxet (Peru); Paxan (Colombia); Paxil (Canada, Costa Rica, Dominican Republic, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama); Paxil CR (Korea); Paxtine (Australia); Paxxet (Israel); Seroxat (Austria, Bulgaria, Colombia, Czech Republic, Denmark, England, Finland, Germany, Hungary, Ireland, Italy, Netherlands, Norway, Peru, Poland, Spain, Sweden); Setine (Taiwan); Tagonis (Germany); XET (India)

Drug Class Antidepressants; SSRIs
Indications Depression, postpartum depression, OCD, panic disorder, anxietal disorders, posttraumatic stress, chronic headache, diabetic neuropathy
Mechanism Selectively inhibits serotonin reuptake
Dosage With Qualifiers Depression—begin 20 mg PO qam, increasing by 10 mg/d qw; max 60 mg/d
OCD—begin 20 mg PO qam, increasing by 10 mg/d qw; max 60 mg/d
Panic disorder—begin 10 mg PO qam, increasing by 10 mg/d qw; max 60 mg/d
Anxietal disorders—begin 20 mg PO qam, increasing by 10 mg/d qw; max 60 mg/d
Posttraumatic stress—begin 20 mg PO qam, increasing by 10 mg/d qw; max 60 mg/d
Chronic headache—begin 10 mg PO qam, increasing by 10 mg/d qw; max 60 mg/d
Diabetic neuropathy—begin 10 mg PO qam, increasing by 10 mg/d qw; max 60 mg/d
NOTE: Taper gradually.

  • Contraindications —hypersensitivity to drug or class, MAOI use within 14 d, thioridazine use

  • Caution —abrupt withdrawal, mania, history of seizures, hepatic or renal dysfunction, narrow-angle glaucoma, suicide risk

Maternal Considerations Depression is common during and after pregnancy, but it often goes unrecognized. Pregnancy is not a reason a priori to discontinue psychotropic drugs. There are no adequate reports or well-controlled studies of paroxetine in pregnant women. Serum concentrations are significantly lower in the third trimester, and about two-thirds of women taking SSRIs during pregnancy for major depression must increase their dose to maintain efficacy. Women should not feel compelled to stop paroxetine when they become pregnant if therapy is indeed indicated. If, after receiving appropriate information they decide to stop, it should be tapered gradually to avoid the abrupt discontinuation syndrome. There is growing clinical experience with the use of paroxetine for the treatment of postpartum depression. Paroxetine is also effective for the treatment of menopause-associated hot flashes.
Side effects include serotonin or withdrawal syndromes, extrapyramidal symptoms, mania, seizures, nausea, diarrhea, headache, somnolence, dizziness, weakness, constipation, tremor, flatulence, anxiety, sweating, decreased libido, blurred vision, appetite changes, and flushing.
Fetal Considerations There are no well-controlled studies in human fetuses. Paroxetine crosses the human placenta, achieving a mean F:M ratio approximating 0.5, a value significantly lower than that observed with citalopram and fluoxetine. Neonatal withdrawal symptoms are documented. Epidemiologic studies are somewhat mixed and suggest confounding factors are at play. A review of independently published analyses and data from a multicenter, population-based case-control study of birth defects suggests that some birth defects occur 2–3.5 × more frequently among the infants of women treated with paroxetine or fluoxetine early in pregnancy compared with other SSRIs (heart defects and specifically septal defects). The risks may not be only structural. In one follow-up study, blunted facial-action responses were observed among infants exposed prenatally to SSRIs, and both prenatal and postnatal exposure was associated with reduced parasympathetic withdrawal and increased parasympathetic cardiac modulation during recovery after an acute noxious event. Given postnatal exposure through breast milk is extremely low and altered biobehavioral pain reactivity is not associated with levels reported for treatment of depression, these findings suggest sustained neurobehavioral effects beyond the newborn period.
Placental perfusion studies suggest fluvoxamine is less efficiently distributed to placental tissue than paroxetine . If the mother discontinues the drug, the model predicts a half-life of fluvoxamine in fetal plasma of 35 h, 3 × longer than paroxetine (10 h). Thus the risk of neonatal withdrawal syndrome due to abrupt discontinuation may be less with fluvoxamine than with paroxetine . Rodent studies are reassuring, revealing no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically.
Breastfeeding Safety There are no adequate reports or well-controlled studies in nursing women. Paroxetine is excreted into human breast milk with the highest concentrations in the hind milk. The relative infant dose is estimated at 1%–3%. However, the levels are variable, and no breastfed child studied to date has had clinically relevant levels detected, suggesting paroxetine is a good selection for breastfeeding women.
Drug Interactions In a controlled study of healthy volunteers, a single dose of pimozide (2 mg) displayed increases in the pimozide AUC of 151% and C max of 62% after paroxetine was titrated to 60 mg daily compared with pimozide alone. Due to the narrow therapeutic index of pimozide and its known ability to prolong the QT interval, concomitant use of pimozide and paroxetine is contraindicated.
Based on the paroxetine mechanism of action and the potential for serotonin syndrome (primarily headache, nausea, sweating, and dizziness), caution is advised when using with other drugs or agents that may affect the serotonergic neurotransmitter systems, such as tryptophan, triptans, SSRIs, linezolid (an antibiotic that is a reversible nonselective MAOI), lithium, tramadol, or St. John’s wort.
There may be a pharmacodynamic interaction between paroxetine and warfarin that causes a bleeding diathesis with unaltered PT. Caution is indicated.
Epidemiologic studies of the case-control and cohort design reveal an association between psychotropic drugs that interfere with serotonin reuptake and upper GI bleeding. Thus patients should be cautioned about the use of such drugs concurrently with paroxetine.
Rare postmarketing reports describe patients with weakness, hyperreflexia, and incoordination after the use of an SSRI (e.g., fluoxetine, fluvoxamine, paroxetine, sertraline ) and sumatriptan.
Cimetidine (300 mg tid) increased steady-state plasma concentrations of paroxetine by approximately 50%. The paroxetine dosage should be guided by clinical effect.
Phenobarbital (100 mg qd × 14 d) reduced the paroxetine (30 mg × 1) AUC and t/2 by 25% and 38%, respectively, compared with paroxetine alone. Because paroxetine exhibits nonlinear pharmacokinetics, the results of this study may not address the case where the two drugs are both being used chronically. No initial dosage adjustment of paroxetine is necessary; any subsequent adjustment should be guided by clinical effect.
Phenytoin (300 mg qd × 14 d) reduces the paroxetine (30 mg × 1) AUC and t/2 by 50% and 35%, respectively, compared with paroxetine alone. When a single phenytoin dose (300 mg PO × 1) was given at paroxetine steady state (30 mg PO qd × 14 d), phenytoin AUC was reduced about 12% compared with phenytoin administered alone. Because both drugs exhibit nonlinear pharmacokinetics, these studies may not apply where both are being used chronically. No initial dosage adjustments are considered necessary when these drugs are co-administered.
Paroxetine is both metabolized by and inhibits CYP2D6. Co-administration with drugs that are metabolized by CYP2D6 (e.g., amitriptyline, fluoxetine, imipramine, nortriptyline ), phenothiazines, and class 1C antiarrhythmics (e.g., encainide, flecainide, propafenone ) should be approached with caution. In most patients (> 90%), CYP2D6 is saturated early during dosing. In one study, paroxetine (20 mg qd) increased the desipramine (100 mg PO × 1) C max , AUC, and t/2 by some two-, five-, and threefold, respectively. In another study, paroxetine (20 mg PO × 1) given to patients stabilized on risperidone (4–8 mg/d) increased the plasma risperidone fourfold, decreased 9-hydroxyrisperidone approximately 10%, and increased the active moiety (the sum of risperidone plus 9-hydroxyrisperidone) 1.4-fold. The effect of paroxetine on the pharmacokinetics of atomoxetine was evaluated when both drugs were at steady state. In healthy but extensive CYP2D6 metabolizers, paroxetine (20 mg qd) increased atomoxetine AUC values sixfold to eightfold and C max threefold to fourfold. The dose of atomoxetine may need to be either reduced or initiated at a lower level when given with paroxetine.
At steady state, when CYP2D6 is essentially saturated, paroxetine clearance is governed by alternative P450 isozymes that, unlike CYP2D6, show no evidence of saturation. Due to the risk of serious ventricular arrhythmias and sudden death potentially associated with elevated plasma levels, paroxetine and thioridazine should not be used together.
Caution is indicated in the co-administration of TCAs because paroxetine may inhibit TCA metabolism. Plasma TCA concentrations should be monitored, and the dose of TCA reduced, if needed.
Because paroxetine is highly bound to plasma protein, use with another drug that is highly protein bound may cause increased free concentrations of the other drug, potentially resulting in adverse events. Conversely, adverse effects could result from displacement of paroxetine by other highly bound drugs.
Due to the potential for serotonin syndrome, caution is advised when paroxetine is used with lithium.
Increases the AUC(0-24), C max , and C min values of procyclidine (5 mg PO qd) by 35%, 37%, and 67%, respectively. The dose of procyclidine should be reduced if anticholinergic effects are seen.
There are reports of elevated theophylline levels associated with paroxetine. Although this interaction has not been formally studied, it is recommended that theophylline levels be monitored when these drugs are used together.
Use of fosamprenavir-ritonavir with paroxetine significantly decreased plasma levels of paroxetine. Any dose adjustment should be guided by clinical effect.
References Bérard A, Chaabane S, Muanda FT, et al. Br J Clin Pharmacol 2016; 82:566-7.
Bérard A, Iessa N, Chaabane S, et al. Br J Clin Pharmacol 2016; 81:589-604.
Bérard A, Ramos E, Rey E, et al. Birth Defects Res B Dev Reprod Toxicol 2007; 80:18-27.
Cole JA, Ephross SA, Cosmatos IS, Walker AM. Pharmacoepidemiol Drug Saf 2007; 16:1075-85.
Hendrick V, Stowe ZN, Altshuler LL, et al. Am J Psychiatry 2003; 160:993-6.
Hostetter A, Stowe ZN, Strader JR Jr, et al. Depress Anxiety 2000; 11:51-7.
Huybrechts KF, Palmsten K, Avorn J, et al. N Engl J Med 2014; 370:2397-407.
Kulin NA, Pastuszak A, Sage SR, et al. JAMA 1998; 279:609-10.
Louik C, Lin AE, Werler MM, et al. N Engl J Med 2007; 356:2675-83.
Matsuoka S, Hori S, Satoh H, Nagamatsu T, et al. Placenta 2017; 58:74-81.
Misri S, Kim J, Riggs KW, Kostaras X. J Clin Psychiatry 2000; 61:828-32.
Nijhuis IJ, Kok-Van Rooij GW, Bosschaart AN. Arch Dis Child Fetal Neonatal Ed 2001; 84:F77.
Oberlander TF, Grunau RE, Fitzgerald C, et al. Pediatrics 2005; 115:411-25.
O’Brien L, Einarson TR, Sarban M, et al. J Obstet Gynaecol Can 2008; 30:696-701.
Rampono J, Proud S, Hackett LP, et al. Int J Neuropsychopharmacol 2004; 7:329-34.
Rayburn WF, Gonzalez CL, Christensen HD, et al. J Matern Fetal Med 2000; 9:136-41.
Reefhuis J, Devine O, Friedman JM, et al. BMJ 2015; 351:h3190.
Stearns V, Beebe KL, Iyengar M, Dube E. JAMA 2003; 289:2827-34.
Stowe ZN, Cohen LS, Hostetter A, et al. Am J Psychiatry 2000; 157:185-9.
Westin AA, Brekke M, Molden E, et al. PLoS One 2017; 12:e0181082.
Summary Pregnancy Category: D
Lactation Category: S (probably)

  • Paroxetine should be used during pregnancy only if the benefit justifies the potential perinatal risk.

  • As there is likely a small increase in cardiac malformations after first-trimester exposure, consideration should be given to a fetal echocardiogram at 20–22 w.

  • Fetal levels are significantly lower those with citalopram and fluoxetine.

Pegfilgrastim — (Neulasta)

International Brand Names

Neulasta (Australia)

Drug Class Hematopoietic agents
Indications Postchemotherapy neutropenia
Mechanism Stimulates granulocyte and macrophage proliferation and differentiation
Dosage With Qualifiers Postchemotherapy neutropenia—6 mg SC × 1 > 24 h after chemotherapy completed
NOTE: Do not give within 14 d of next chemotherapy course.

  • Contraindications —hypersensitivity to drug or class, hypersensitivity to E. coli proteins

  • Caution —myelodysplasia, sickle cell disease, myeloid malignancy

Maternal Considerations There is no published experience with pegfilgrastim in pregnancy.
Side effects include thrombocytopenia, splenic rupture, splenomegaly, ARDS, muscular and skeletal pain, headache, abdominal pain, flank pain, elevated LDH or uric acid or alkaline phosphatase, and injection site reaction.
Fetal Considerations There are no reports or well-controlled studies in human fetuses. It is unknown whether pegfilgrastim crosses the human placenta. Rodent studies reveal increased postimplantation resorption and abortion rates, and IUGR often at doses in excess of that recommended and in association with maternal toxicity.
Breastfeeding Safety There is no published experience in pregnancy or during lactation. The large size of the molecule and poor oral bioavailability suggest little will be found in milk.
Drug Interactions Drugs such as lithium may potentiate the release of neutrophils; patients receiving lithium and pegfilgrastim require frequent neutrophil counts.
References No relevant publications.
Summary Pregnancy Category: C
Lactation Category: S (likely)

  • Pegfilgrastim should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

Peginterferon alfa-2b — (Pegintron, Sylatron)

International Brand Names

None identified.

Drug Class Antivirals; Immunomodulators
Indications HCV infection
Mechanism Inhibits viral replication via multiple antiviral, antiproliferative, and immunomodulatory effects
Dosage With Qualifiers Chronic HCV infection—1 mg/kg/w SC × 1 y
NOTE: Anemia and neutropenia dosing; restricted access in the United States.

  • Contraindications —hypersensitivity to drug or class, autoimmune hepatitis, decompensated hepatic disease, combination therapy during pregnancy with ribavirin or males with pregnant female partners

  • Caution —myelosuppression, diabetes mellitus, psychiatric disorders, thyroid disease, colitis, cardiac or pulmonary disease, ophthalmologic disorders

Maternal Considerations Interferons bind to specific cell surface membrane receptors to initiate a complex sequence of intracellular events. Alfa interferons, including peginterferon alfa-2b, may cause or aggravate fatal or life-threatening neuropsychiatric, autoimmune, ischemic, and infectious disorders. Patients should be monitored closely with periodic clinical and laboratory evaluations. Therapy should be discontinued in women with persistently severe or worsening signs or symptoms. In many, but not all, instances, these disorders resolve after discontinuation. Cynomolgus monkeys treated SC with doses at multiples of the MRH experienced irregular menstrual cycles.
Side effects include psychosis, suicidal ideation, anemia, neutropenia, thrombocytopenia, thyroid dysfunction, cardiomyopathy, arrhythmias, MI, pancreatitis, retinal thrombosis, retinal hemorrhage, headache, N/V, fatigue, rigors, fever, depression, abdominal pain, diarrhea, and injection site reactions.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether peginterferon alfa-2b crosses the human placenta. There are only two described pregnancies inadvertantly treated for chronic hepatitis B with peginterferon alfa 2-b during the first trimester. Both offspring did well. High doses of native interferon alfa-2b were associated with abortion in cynomolgus monkeys. Combination therapy with ribavirin may cause birth defects and/or fetal mortality.
Breastfeeding Safety There is no published experience during lactation. It is unknown whether peginterferon alfa-2b enters human breast milk. Unlike HIV, breastfeeding is not considered a risk for the newborns of HCV-infected women.
Drug Interactions No clinically relevant interactions identified.
References Atasoy HI, Sirmatel P, Sirmatel F. J Matern Fetal Neonatal Med 2017; 30:745-7.
Summary Pregnancy Category: C/X in combination with ribavirin
Lactation Category: U

  • Peginterferon alfa-2b should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

  • Co-administration with ribavirin should be avoided during pregnancy and in females and female partners of male patients.

Pemirolast ophthalmic — (Alamast)

International Brand Names

Alegysal (China, Indonesia, Korea, Philippines, Taiwan); Pemirox (Hong Kong, Thailand)

Drug Class Allergy; Mast cell stabilizers; Ophthalmics
Indications Allergic conjunctivitis
Mechanism Inhibits mast cell degranulation
Dosage With Qualifiers Allergic conjunctivitis—1–2 gtt each eye qid for max 4 w

  • Contraindications —hypersensitivity to drug or class

  • Caution —unknown

Maternal Considerations There is no published experience with pemirolast in pregnancy.
Side effects include headache, dry eyes, burning or other ocular discomfort, and respiratory symptoms.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether pemirolast crosses the human placenta. However, considering the dose and route, it is unlikely the maternal systemic concentration would achieve a clinically relevant level. Rodent teratogenicity studies revealed skeletal abnormalities following the systemic administration of doses 20,000 × or more above the MRHD.
Breastfeeding Safety There is no published experience during lactation. It is unknown whether pemirolast enters human breast milk. However, considering the dose and route, it is unlikely the breastfed neonate will ingest clinically relevant amounts. It is concentrated in rodent milk.
Drug Interactions No clinically relevant interactions identified.
References There are no current relevant references.
Summary Pregnancy Category: C
Lactation Category: S (likely)

  • Pemirolast should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

Penciclovir topical — (Denavir)

International Brand Names

Vectavir (Costa Rica, Dominican Republic, El Salvador, Germany, Guatemala, Honduras, Israel, Nicaragua, Panama, South Africa)

Drug Class Antivirals; Dermatologics
Indications Herpes labialis
Mechanism Inhibits DNA polymerase
Dosage With Qualifiers Herpes labialis—apply q2h × 4 d

  • Contraindications —hypersensitivity to drug or class

  • Caution —immune deficiency

Maternal Considerations There is no published experience with penciclovir in pregnancy. Because penciclovir is poorly absorbed when given orally, it is typically used as a topical treatment. It is the active ingredient in the cold sore medications Denavir, Vectavir, and Fenivir . There is little systemic absorption after topical application. Famciclovir is a prodrug of penciclovir with improved oral bioavailability.
Side effects include headache, pruritus, taste changes, and erythema.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether penciclovir crosses the human placenta; it does apparently cross the rodent placenta. However, considering the dose and route, it is unlikely the maternal systemic concentration will reach clinically relevant levels. Rodent studies are reassuring, revealing no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically.
Breastfeeding Safety There is no published experience in nursing women. It is unknown whether penciclovir enters human breast milk. However, considering the dose and route, it is unlikely the breastfed neonate would ingest clinically relevant amounts. One report suggests it rapidly is excreted into and then cleared from rodent breast milk.
Drug Interactions No clinically relevant interactions identified.
References Choi WS, Im GJ, Kim DK, et al. Drug Metab Dispos 2001; 29:945-9.
Patel VM, Schwartz RA, Lambert WC. J Eur Acad Dermatol Venereol 2017; 31:1440-6.
Summary Pregnancy Category: B
Lactation Category: S (likely)

  • Penciclovir should be used during pregnancy only if the benefit justifies the potential perinatal risk.

Penicillamine — (Cuprimine; Depen; Mercaptyl)

International Brand Names

Adaleen (Mexico); Artamin (Austria, Korea, Malaysia); Atamir (Denmark); Cuprenil (Bulgaria, Hungary); Cuprimine (Canada, Malaysia, Netherlands, Norway, Sweden, Taiwan, Thailand); Cuprimune (Argentina, Brazil); Cupripen (Spain, Uruguay); Depen (Canada); Distamine (England, Ireland, Netherlands, Switzerland); D-Penil (Peru); Kelatin (Belgium, Netherlands); Kelatine (Portugal); Metalcaptase (Germany, Japan); Pendramine (England); Penicilamina (Chile); Penicillamine (South Africa); Sufortanon (Spain)

Drug Class Antirheumatics; Cystine-depleting agents
Indications Wilson’s disease, cystinuria, rheumatoid arthritis, heavy-metal poisoning
Mechanism Unknown for arthritis; chelates copper
Dosage With Qualifiers Wilson’s disease—250–500 mg PO tid or qid 30 min before meals
Cystinuria—250–1000 mg PO qid 30 min before meals
Rheumatoid arthritis (unresponsive to conventional agents)—250 mg PO bid or tid 30 min before meals; requires 3–6 mo for max effect
Heavy-metal poisoning—125–600 mg PO tid 30 min before meals

  • Contraindications —hypersensitivity to drug or class, gold salt, antimalarial or immunosuppressant use, history of penicillamine -related anemia

  • Caution —renal dysfunction, penicillin allergy

Maternal Considerations There are no adequate reports or well-controlled studies in pregnant women. Penicillamine is contraindicated during pregnancy except to treat Wilson’s disease and some cases of cystinuria. The published experience is limited to case reports and small series. Recurrent abortions are common in women with untreated Wilson’s disease. Successful pregnancies and uneventful full-term delivery may occur with treatment and in presymptomatic patients. Pregnancy does not appear to have an adverse effect on the clinical course of Wilson’s disease. Zinc, which induces intestinal cell metallothionein that binds copper and prevents its transfer into blood, may be a suitable adjunct or alternative therapy.
Side effects include thrombocytopenia, aplastic anemia, agranulocytosis, pancreatitis, exfoliative dermatitis, myasthenia gravis, SLE-like syndrome, rash, pruritus, N/V, dyspepsia, proteinuria, glossitis, taste changes, stomatitis, and hirsutism.
Fetal Considerations There are no well-controlled studies in human fetuses. Penicillamine apparently crosses the human placenta, as congenital cutis laxa and associated defects such as micrognathia, contractures, and CNS abnormalities are reported in neonates of treated women. Teratogenicity has otherwise not been reported in women receiving low-dose penicillamine and zinc sulfate. In one series of 20 pregnancies with first-trimester maternal chelator therapy, no major birth defects were observed. Three experienced spontaneous abortion, and one pregnancy was electively terminated. Penicillamine is teratogenic in rodents at doses 6 × the MRHD. Adverse effects include skeletal deformities, cleft palate, and embryotoxicity.
Breastfeeding Safety There is no published experience in nursing women. It is unknown whether penicillamine enters human breast milk, though the pharmacology suggests it will. Most recommend not breastfeeding if treatment is necessary.
Drug Interactions No clinically relevant interactions identified.
References Brewer GJ, Johnson VD, Dick RD, et al. Hepatology 2000; 31:364-70.
Dathe K, Beck E, Schaefer C. Reprod Toxicol 2016; 65:39-45.
Furman B, Bashiri A, Wiznitzer A, et al. Eur J Obstet Gynecol Reprod Biol 2001; 96:232-4.
Martinez-Frias ML, Rodriguez-Pinilla E, Bermejo E, Blanco M. Am J Med Genet 1998; 76:274-5.
Pinter R, Hogge WA, McPherson E. Am J Med Genet A 2004; 128A:294-8.
Sinha S, Taly AB, Prashanth LK, et al. J Neurol Sci 2004; 217:37-40.
Summary Pregnancy Category: D
Lactation Category: NS (possibly)

  • Penicillamine should be used during pregnancy only if the benefit justifies the potential perinatal risk.

  • It is probably best to avoid breastfeeding.

Penicillin G, aqueous

Drug Class Antibiotics; Penicillins
Indications Systemic infection (moderate to severe), anthrax, syphilis
Mechanism Bactericidal—inhibits cell wall mucopeptide synthesis
Dosage With Qualifiers Systemic infection (moderate to severe)—4 million U IM/IV q4h
Anthrax— oral, GI, or inhalational: 4 million U IV q4h as part of a multidrug regimen × 60 d; cutaneous: 4 million U IV q4h × 7–10 d, then switch to PO for 60 d
Neurosyphilis—18 million–24 million U qd IV × 10–14 d
NOTE: Renal dosing.
NOTE: Bicillin combines penicillin G and benzathine penicillin G.

  • Contraindications —hypersensitivity to drug or class

  • Caution —renal dysfunction, cephalosporin allergy, seizure disorder

Maternal Considerations Penicillin G is typically given parenterally because it is unstable in gastric hydrochloric acid. Because it is given IV, higher tissue concentrations are achieved than with penicillin VK (phenoxymethylpenicillin). There is a long clinical experience with penicillin G during pregnancy that is reassuring. Vaginal GBS colony counts fall rapidly after intrapartum penicillin G, which explains in part the effectiveness of chemoprophylaxis. It is as effective as cephalothin for the prevention of post–cesarean section infection.
Side effects include thrombocytopenia, seizures, Stevens-Johnson syndrome, hemolytic anemia, neutropenia, interstitial nephritis, N/V, abdominal pain, diarrhea, rash, fever, and thrombophlebitis.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. Most penicillins cross the human placenta to some extent. Penicillin G is efficiently transferred across the horse placenta. Rodent studies are reassuring, revealing no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically.
Breastfeeding Safety There are no adequate reports or well-controlled studies in nursing women. Only trace amounts of penicillin G enter human breast milk. It is generally considered compatible with breastfeeding.
Drug Interactions Tetracycline, a bacteriostatic antibiotic, may antagonize the bactericidal effect of penicillin, and use of these drugs together should be avoided.
Use with probenecid increases and prolongs serum penicillin levels by decreasing the apparent volume of distribution and slowing the rate of excretion by competitively inhibiting renal tubular secretion of penicillin .
References Matsuda S. Biol Res Pregnancy Perinatol 1984; 5:57-60.
McNanley AR, Glantz JC, Hardy DJ, Vicino D. Am J Obstet Gynecol 2007; 197:583.e1-4.
Murchie TA, Macpherson ML, LeBlanc MM, et al. Equine Vet J 2006; 38:520-5.
Rudge MV, Atallah AN, Peraçoli JC, et al. Acta Obstet Gynecol Scand 2006; 85:945-8.
Summary Pregnancy Category: B
Lactation Category: S

  • Penicillin G has been used for decades during pregnancy and lactation.

  • Though there is little objective study, it is generally considered safe for listed indications.

  • Penicillin resistance is a growing disadvantage.

Penicillin G, benzathine — (Bicillin LA; Pen-Di-Ben; Permapen)

International Brand Names

Benzacillin (Korea); Benzanil Simple (Mexico); Benzetacil (Brazil, Ecuador, Mexico, Spain); Benzetacil A.P. (Mexico); Benzetacil L.A. (Argentina, Colombia, Ecuador, Paraguay, Peru, Uruguay, Venezuela); Benzilfan (Mexico); Bicillin L-A (New Zealand); Bicillin LA 1.2 (South Africa); Bicillin LA 2.4 (South Africa); Cepacilina (Spain); Diaminocillina (Italy); Durabiotic (Israel); Extencilline (France); Lentopenil (Mexico); Lutecilina (Colombia); Penadur (Switzerland); Penadur L-A (Thailand); Penadur L.A. (Belgium, Greece, Switzerland); Penadur - LA (Puerto Rico); Penadur LA (Hong Kong, Indonesia, Israel, Malaysia, Philippines, South Africa); Pencom (India); Pen Di Ben (Argentina); Pen-Di-Ben (Dominican Republic, El Salvador, Guatemala, Honduras, Nicaragua, Panama); Penidural (Netherlands); Penidure LA 6 (India); Penidure LA 12 (India); Penidure LA 24 (India); Penilente (South Africa); Penilente - LA (South Africa); Penretard (Brazil); Retarpen (Austria, Costa Rica, Dominican Republic, Ecuador, El Salvador, Guatemala, Honduras, Israel, Malaysia, Nicaragua, Panama, Singapore); Tardocillin 1200 (Germany); Wycillina A P (Italy); Zalpen (Philippines)

Drug Class Antibiotics; Penicillins
Indications Syphilis, group A streptococcus infection
Mechanism Bactericidal—inhibits cell wall mucopeptide synthesis
Dosage With Qualifiers Syphilis (primary, secondary or early latent)—2.4 million U IM × 1 if < 1 y duration, qw × 3 if > 1 y duration (late latent, unknown duration, tertiary)
Group A streptococcus infection—1.2 million U IM × 1
NOTE: Bicillin combines penicillin G and benzathine penicillin G.

  • Contraindications —hypersensitivity to drug or class

  • Caution —renal dysfunction, cephalosporin allergy, seizure disorder

Maternal Considerations Benzathine penicillin G is slowly absorbed after IM injection and subsequently hydrolyzed to benzylpenicillin. It is the drug of choice when prolonged low concentrations of benzylpenicillin are required, allowing for prolonged antibiotic action over 2–4 w. There are no adequate reports or well-controlled studies in pregnant women. Benzathine penicillin G remains the drug of choice for syphilis during pregnancy. However, Bicillin C-R (contains 1.2 million U of benzathine penicillin G and 1.2 million units of procaine penicillin G ) is not recommended for treating syphilis because it contains only half the recommended dose of benzathine penicillin G. Medication errors have occurred, and as a result changes in product packaging were made; specifically, the statement “Not for the Treatment of Syphilis” has been added in red text to both the Bicillin CR and Bicillin CR 900/300 syringe labels. There is some concern benzathine penicillin G may not prevent neurosyphilis, but the overall risk appears low. Partner notification is mandatory to prevent the spread of the disease. About 40% of patients experience a Jarisch-Herxheimer reaction; treated women should be warned of the possibility and monitored closely for the first 48 h. Benzathine penicillin G-penicillin G suspension (Bicillin L-A) 2.4 million U IM is insufficient as sole therapy for group B streptococcal prophylaxis.
Side effects include thrombocytopenia, seizures, rash, Stevens-Johnson syndrome, fever, hemolytic anemia, neutropenia, interstitial nephritis, N/V, abdominal pain, diarrhea, and thrombophlebitis.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. Benzathine penicillin G crosses the placenta. Treatment reduces the overall incidence of congenital syphilis from 3.4% to 0.2%. The incidence of congenital syphilis is also lower in women treated prior to 28 w compared to those treated after 28 w, and lower in women receiving two courses of therapy compared with one. It is also lower in pregnancies treated with benzathine penicillin G rather than other antibiotics.
The currently recommended dose of benzathine penicillin G is effective for preventing congenital syphilis in most settings, although some additional study regarding dose modification is needed. Rodent studies of benzathine penicillin G are reassuring, revealing no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically.
Breastfeeding Safety There are no adequate reports or well-controlled studies in nursing women. Only trace amounts of benzathine penicillin G enter human breast milk. It is generally considered compatible with breastfeeding.
Drug Interactions Tetracycline, a bacteriostatic antibiotic, may antagonize the bactericidal effect of penicillin, and use of these drugs together should be avoided.
Use with probenecid increases and prolongs serum penicillin levels by decreasing the apparent volume of distribution and slowing the rate of excretion by competitively inhibiting renal tubular secretion of penicillin .
References Hong FC, Wu XB, Yang F, et al. Clin Infect Dis 2017; 65:588-94.
Matsuda S. Biol Res Pregnancy Perinatol 1984; 5:57-60.
Myles TD, Elam G, Park-Hwang E, Nguyen T. Obstet Gynecol 1998; 92:859-64.
Nathan L, Bawdon RE, Sidawi JE, et al. Obstet Gynecol 1993; 82:338-42.
Pinette MG, Thayer K, Wax JR, et al. J Matern Fetal Neonatal Med 2005; 17:333-5.
Sheffield JS, Sanchez PJ, Morris G, et al. Am J Obstet Gynecol 2002; 186:569-73.
Watson-Jones D, Gumodoka B, Weiss H, et al. J Infect Dis 2002; 186:948-57.
Weeks JW, Myers SR, Lasher L, et al. Obstet Gynecol 1997; 90:240-43.
Wendel GD Jr, Sheffield JS, Hollier LM, et al. Clin Infect Dis 2002; 35(Suppl 2):S200-9.
Summary Pregnancy Category: B
Lactation Category: S

  • Benzathine penicillin G has been used for decades during pregnancy and lactation.

  • Initiate treatment of syphilis-seropositive pregnant women before 28 gestational weeks.

  • The risk of treating pregnant women with benzathine penicillin G to prevent congenital syphilis appears very low and does not outweigh its benefits.

  • It remains the drug of choice for the treatment of syphilis.

Penicillin G, procaine — (Crysticillin AS; Duracillin AS; Pfizerpen AS; Provaine Penicillin; Wycillin)

International Brand Names

Aqucilina (Spain); Farmaproina (Spain); Fradicilina 600 (Spain); Kemopen (Indonesia); Novocillin (South Africa); Penicil (Mexico); Procapen (Finland); Procillin (South Africa)

Drug Class Antibiotics; Penicillins
Indications Systemic infection (moderate to severe), pneumococcal pneumonia, gonorrhea, syphilis
Mechanism Bactericidal—inhibits cell wall mucopeptide synthesis
Dosage With Qualifiers Systemic infection (moderate to severe)—0.6 million–1.2 million U IM qd
Pneumococcal pneumonia—0.6 million–1.2 million U IM qd
Uncomplicated gonorrhea—4.8 million U IM × 1 30 min after 1 g probenecid PO
Neurosyphilis (alternative to aqueous penicillin)—2.4 million U IM qd plus probenecid 500 mg PO qid, each × 10–14 d

  • Contraindications —hypersensitivity to drug or class, IV injection

  • Caution —renal dysfunction, cephalosporin allergy, seizure disorder

Maternal Considerations Procaine penicillin G is a combination of benzylpenicillin with the local anesthetic agent procaine. It is slowly absorbed after IM administration and hydrolyzed to benzylpenicillin and thus used to achieve prolonged but low concentrations of benzylpenicillin. The combination seeks to reduce the pain and discomfort associated with a large IM injection of penicillin. There are no adequate reports or well-controlled studies in pregnant women. Procaine penicillin G may be used in place of benzathine penicillin G to treat syphilis, but it has no medical advantage.
Side effects include thrombocytopenia, seizures, rash, Stevens-Johnson syndrome, Jarisch-Herxheimer reaction, myocardial depression, hemolytic anemia, neutropenia, interstitial nephritis, N/V, abdominal pain, diarrhea, fever, sterile abscess, vasodilation, and thrombophlebitis.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. Most penicillins cross the human placenta to some extent. Procaine penicillin G should behave the same as benzathine penicillin G. The large clinical experience is reassuring, as are the rodent studies, which reveal no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically.
Breastfeeding Safety There are no adequate reports or well-controlled studies in nursing women. Only trace amounts of procaine penicillin G enter human breast milk. It is generally considered compatible with breastfeeding.
Drug Interactions Use with bacteriostatic antibiotics (e.g., erythromycin , tetracycline ) may reduce the bactericidal effects of penicillins by slowing the rate of bacterial growth. There are few clinical situations in which the concurrent use of “static” and “cidal” antibiotics are indicated. In those circumstances, using adequate doses and beginning the penicillin therapy first should minimize the risks.
Penicillin blood levels may be prolonged by use with probenecid, which blocks the renal tubular secretion of penicillin .
Displacement from plasma protein binding sites will elevate the free penicillin levels.
References Matsuda S. Biol Res Pregnancy Perinatol 1984; 5:57-60.
Paryani SG, Vaughn AJ, Crosby M, Lawrence S. J Pediatr 1994; 125:471-5.
Summary Pregnancy Category: B
Lactation Category: S

  • Procaine penicillin G has been used for decades during pregnancy and lactation.

  • Though there is little objective study, it is generally considered safe for listed indications.

  • Penicillin resistance is a growing disadvantage.

Penicillin VK — (Pen-Vee K; Veetids)

International Brand Names

Abbocillin VK (Australia); Anapenil (Mexico); Apo-Pen-VK (Canada); Arcasin (Germany); Beapen (Malaysia); Cilacil (Argentina); Cliacil (Argentina); Crystapen V (India); Distaquaine V-K (England); DuraPenicillin (Germany); Fenocin (Indonesia); Fenoxcillin (China, Denmark); Fenoxypen (Norway, Sweden); Isocillin (Germany); Kavipen (Mexico); Len V.K. (South Africa); L.P.V. (Australia); Megacilina Oral (Peru); Megacillin Oral (China, Germany); Milcopen (Finland); Nadopen-V (Canada); Newcillin (Japan); Novopen-VK (Canada); Novo-VK (South Africa); Oracilin (Brazil); Oracillin VK (South Africa); Orvek (Israel); Ospen (China, France, Malaysia, Singapore, Uruguay, Venezuela); Ospen 250 (Austria); Penbeta (Germany); Penoral (Argentina); Penoxil (Malaysia); Pentacillin (Philippines); Pentid (Argentina); Pentranex (Philippines); Pen V (Hong Kong); Pen Vee K (Colombia); Pen-Vi-K (Mexico); Primcillin (Denmark); Rafapen V-K (Israel); Robicillin VK (Israel); Rocilin (Denmark); Servipen-V (Thailand); Trepopen VK (Philippines); V-Cil-K (Ireland, Puerto Rico, South Africa); Vepicombin (Denmark); V-Kal-K (Japan); V-Pen (Israel); V-Penicillin Kalium (Japan)

Drug Class Antibiotics; Penicillins
Indications Group A streptococcus infection, pneumococcal pneumonia, or rheumatic fever prophylaxis
Mechanism Bactericidal—inhibits cell wall mucopeptide synthesis
Dosage With Qualifiers Group A streptococcus infection—250–500 mg PO q6–8 h × 10 d
Pneumococcal pneumonia prophylaxis—250 mg PO bid
Rheumatic fever prophylaxis—250 mg PO bid
NOTE: To be taken 1 h before or 2 h after meals.

  • Contraindications —hypersensitivity to drug or class

  • Caution —renal dysfunction, cephalosporin allergy, seizure disorder, PKU

Maternal Considerations Penicillin VK is the orally active form of penicillin. It is less active than benzylpenicillin and is only appropriate in circumstances where high tissue concentrations are not required. There are no adequate reports or well-controlled studies in pregnant women. However, there is a long clinical experience that is reassuring.
Side effects include thrombocytopenia, seizures, rash, Stevens-Johnson syndrome, hemolytic anemia, neutropenia, interstitial nephritis, N/V, abdominal pain, diarrhea, pseudomembranous colitis, and fever.
Fetal Considerations There are no adequate reports or well-controlled studies of penicillin VK in human fetuses. Most penicillins cross the human placenta to some extent. The large clinical experience is reassuring, as are the rodent studies, which reveal no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically.
Breastfeeding Safety There are no adequate reports or well-controlled studies in nursing women. Penicillin VK is excreted into breast milk and may be detected in the urine of breastfeeding infants. However, it is generally considered compatible with breastfeeding.
Drug Interactions Use with bacteriostatic antibiotics (e.g., erythromycin, tetracycline ) may reduce the bactericidal effects of penicillins by slowing the rate of bacterial growth. There are few clinical situations in which the concurrent use of “static” and “cidal” antibiotics are indicated. In those circumstances, using adequate doses and beginning the penicillin therapy first should minimize the risks.
Penicillin blood levels may be prolonged by use with probenecid, which blocks the renal tubular secretion of penicillin .
Displacement from plasma protein binding sites will elevate the free penicillin levels.
References Dencker BB, Larsen H, Jensen ES, et al. Clin Microbiol Infect 2002; 8:196-201.
Matsuda S. Biol Res Pregnancy Perinatol 1984; 5:57-60.
Summary Pregnancy Category: B
Lactation Category: S

  • Penicillin VK has been used for decades during pregnancy and lactation.

  • Though there is little objective study, it is generally considered safe for listed indications.

  • Penicillin resistance is a growing disadvantage.

Pentamidine — (Nebupent; Pentam 300)

International Brand Names

Benambex (Japan); Pentacarinat (Argentina, Bulgaria, Canada, Czech Republic, France, Hungary, Ireland, Israel, New Zealand, Peru, Poland, Puerto Rico, Slovenia, South Africa, Thailand, Turkey)

Drug Class Antiprotozoals
Indications PCP prophylaxis and treatment
Mechanism Unknown
Dosage With Qualifiers PCP prophylaxis—300 mg NEB q4w
PCP treatment—4 mg/kg IV/IM qd × 14–21 d

  • Contraindications —hypersensitivity to drug or class

  • Caution —hepatic or renal dysfunction, hypertension, hypotension, leukopenia, hypoglycemia

Maternal Considerations There are no adequate reports or well-controlled studies of pentamidine in pregnant women. Withholding appropriate PCP prophylaxis can adversely affect maternal and fetal outcomes. PCP during pregnancy may have a more aggressive course with increased morbidity and death. Maternal and fetal outcomes are poor. Treatment with sulfamethoxazole-trimethoprim may improve outcome compared with other therapies. Aerosolized pentamidine does not appear to pose a significant risk to pregnant health care workers. Pentamidine is also the current treatment of choice for maternal sleeping sickness caused by human African trypanosomiasis.
Side effects include renal failure, leukopenia, thrombocytopenia, hypoglycemia, Stevens-Johnson syndrome, bronchospasm, fatigue, nausea, dyspepsia, decreased appetite, fever, rash, cough, and dizziness.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. There are no published human reports of concern, and human placental transport of pentamidine across the isolated cotyledon is limited. Pentamidine crosses the rodent placenta and penetrates all fetal compartments. Rodent studies are in general reassuring, revealing embryotoxicity but no teratogenicity or IUGR.
Breastfeeding Safety There is no published experience in nursing women. It is unknown whether pentamidine enters human breast milk. Breastfeeding is contraindicated in HIV-infected nursing women where formula is available to reduce the risk of neonatal transmission.
Drug Interactions No clinically relevant interactions identified.
References Ahmad H, Mehta NJ, Manikal VM, et al. Chest 2001; 120:666-71.
Fortunato SJ, Bawdon RE. Am J Obstet Gynecol 1989; 160:759-61.
Harstad TW, Little BB, Bawdon RE, et al. Am J Obstet Gynecol 1990; 163:912-6.
Ito S, Koren G. Chest 1994; 106:1460-2.
Little BB, Harstad TH, Bawdon RE, et al. Am J Obstet Gynecol 1991; 164:927-30.
Pohlig G, Bernhard SC, Blum J, et al. PLoS Negl Trop Dis. 2016; 10:e0004363.
Summary Pregnancy Category: C
Lactation Category: NS

  • Pentamidine should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

  • Withholding appropriate PCP prophylaxis can adversely affect maternal and fetal outcomes.

Pentazocine — (Talwin)

International Brand Names

Peltazon (Japan); Pentagin (Japan); Rafazocine X (Israel); Sosegon (Japan); Talwin (Canada)

Drug Class Analgesics, narcotic; Narcotic agonist-antagonists
Indications Moderate to severe pain, obstetric analgesia, anesthesia adjunct
Mechanism Binds opiate receptors, producing both agonist and antagonist effects
Dosage With Qualifiers Moderate to severe pain—30 mg IM/IV/SC q3–4 h prn; max 60 mg/dose
Obstetric analgesia—20 mg IV (or 30 mg IM) q2–4 h prn
Anesthesia adjunct—20 mg IV (or 30 mg IM) q2–4 h prn
NOTE: SC injections may cause severe tissue damage and are best avoided.
NOTE: May be combined with naloxone or acetaminophen.

  • Contraindications —hypersensitivity to drug or class

  • Caution —opiate dependence; head injury; hepatic, renal, or pulmonary dysfunction; post MI

Maternal Considerations Pentazocine is a potent analgesic; 30–45 mg is equianalgesic to morphine 10 mg and meperidine 75–100 mg. There are no adequate reports or well-controlled studies in pregnant women. Pentazocine is a poor choice for labor analgesia because of greater maternal respiratory depression than the alternatives. Some patients receiving narcotics, including methadone, experience withdrawal symptoms because pentazocine is a weak narcotic antagonist. A single 15-mg dose of IV pentazocine after delivery can reduce both the incidence and severity of pruritus in women who receive subarachnoid opioids during cesarean delivery.
Side effects include addiction, respiratory depression, hypotension, seizures, granulocytopenia, N/V, dizziness, euphoria, hallucinations, sedation, headache, constipation, blurred vision, miosis, tremor, irritability, facial edema, flushing, and pruritus.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. Pentazocine crosses the human placenta. The addictive combination of pentazocine and tripelennamine (T’s and blues) remains popular in some locales. Infants of women who use T’s and blues throughout pregnancy have interactive deficits and withdrawal similar to methadone -addicted newborns. In general, rodent studies are reassuring, revealing no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically. A single study in hamsters suggested an increased risk of CNS malformations.
Breastfeeding Safety There is no published experience in nursing women. Although it is unknown whether pentazocine enters human breast milk, the clinical experience is reassuring.
Drug Interactions Ethanol should be avoided because of the potential for increased CNS depressant effects.
Increased toxicity when combined with tripelennamine, phenothiazines, sedatives, and hypnotics.
References Chasnoff IJ, Hatcher R, Burns WJ, Schnoll SH. Dev Pharmacol Ther 1983; 6:162-9.
Geber WF, Schramm LC. Am J Obstet Gynecol 1975; 123:705-13.
Hirabayashi M, Doi K, Imamachi N, et al. Anesth Analg 2017; 124:1930-4.
Wahab SA, Askalani AH, Amar RA, et al. Int J Gynaecol Obstet 1988; 26:75-80.
Summary Pregnancy Category: C
Lactation Category: U

  • Pentazocine should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

  • There are less addictive but equally effective analgesics available for most indications.

Pentobarbital — (Carbrital; Nembutal)

International Brand Names

Dormital (Uruguay); Embutal (Argentina); Medinox Mono (Germany); Mintal (Japan); Sombutol (Finland)

Drug Class Anticonvulsants; Anxiolytics; Barbiturates; Sedatives
Indications Sedation, insomnia, barbiturate coma
Mechanism Depresses the sensory and motor cortex and alters cerebellar function
Dosage With Qualifiers Sedation—20–40 mg PO bid to qid
Insomnia—100 mg PO qhs prn for short-term therapy
Barbiturate coma—load with 5 mg/kg over 30 min, then 1–3 mg/kg/h IV; systemic arterial BP must be supported (e.g., inotropic support)

  • Contraindications —hypersensitivity to drug or class, decreased respiratory function, porphyria

  • Caution —hepatic dysfunction, history of substance abuse, suicidal ideation

Maternal Considerations Barbiturates produce CNS mood alteration ranging from excitation to sedation to hypnosis and deep coma. As a sleep aid, barbiturates are of limited value beyond the short term as they lose effectiveness after 1–2 w. There are superior agents that have less effect on the sleep cycle. There are no adequate reports or well-controlled studies of pentobarbital in pregnant women. Hypnotic doses do not impair uterine activity during labor.
Side effects include addiction, respiratory depression, Stevens-Johnson syndrome, SLE, angioedema, confusion, agitation, hyperkinesias, ataxia, CNS depression, hallucinations, dizziness, apnea, bradycardia, hypotension, syncope, N/V, constipation, and headache.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. Pentobarbital rapidly crosses the human placenta. The highest concentrations are found in placenta, liver, and brain. Its administration during labor can cause neonatal respiratory depression. Preterm infants are particularly susceptible, and resuscitation equipment should be available. Chronic use during the third trimester can yield addicted neonates who have an extended withdrawal syndrome. Retrospective, case-control studies suggest a connection between barbiturates and an increased risk of fetal abnormalities. However, there are no such reports specifically for pentobarbital, and the rodent studies are reassuring. There is a single study suggesting a reduction in fertility.
Breastfeeding Safety There are no adequate reports or well-controlled studies in nursing women. Only small amounts of pentobarbital enter human breast milk, and it is generally considered compatible with breastfeeding.
Drug Interactions Most reports of clinically significant drug interactions with barbiturates involve phenobarbital. However, the application of these data to other barbiturates may be valid.
Barbiturates may induce liver microsomal enzymes, increasing the metabolism and decreasing the anticoagulant response to oral anticoagulants (e.g., acenocoumarol, dicumarol, phenprocoumon, coumadin ). Anticoagulant dose adjustments may be necessary if barbiturates are added or withdrawn.
Barbiturates enhance the metabolism of exogenous corticosteroids, probably through the induction of liver microsomal enzymes. A dose adjustment may be required if barbiturates are added or withdrawn.
Phenobarbital may interfere with the oral absorption of griseofulvin. The effect of decreased blood levels of griseofulvin on therapeutic response has not been established. It is preferable to avoid their use together.
Phenobarbital may shorten the t/2 of doxycycline for as long as 2 w after barbiturate discontinuation, probably through the induction of liver microsomal enzymes that metabolize doxycycline. The clinical response to doxycycline should be monitored closely if the two drugs are used together.
The effect of barbiturates on phenytoin metabolism appears variable. Some note an accelerating effect, whereas others report no effect. Because the effect is unpredictable, phenytoin and barbiturate blood levels should be monitored more frequently if used together.
Valproate and valproic acid appear to decrease barbiturate metabolism; thus barbiturate blood levels should be monitored and dose adjustments made as appropriate.
Use with other CNS depressants, including other sedatives or hypnotics, antihistamines, tranquilizers, or ethanol, may produce additive depressant effects.
MAOIs prolong the effects of barbiturates probably by inhibiting the metabolism of the barbiturate.
Pretreatment with or concurrent use of phenobarbital may decrease the effect of estradiol by increasing its metabolism. There are reports of women treated with AEDs (e.g., phenobarbital ) becoming pregnant while taking oral contraceptives. An alternate contraceptive method should be suggested.
Pentobarbital is CYP2A6 inducer and may decrease the serum concentration of CYP2A6 substrates requiring dosage adjustments.
References Ito T, Ingalls TH. Arch Environ Health 1981; 36:316-20.
Summary Pregnancy Category: D
Lactation Category: S

  • Pentobarbital should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

  • For all but coma, there are other agents with superior safety profiles during pregnancy.

Pentosan polysulfate sodium — (Elmiron)

International Brand Names

None identified.

Drug Class Genitourinary
Indications Interstitial cystitis
Mechanism Unknown
Dosage With Qualifiers Interstitial cystitis—100 mg PO tid 1 h before or 2 h after meals

  • Contraindications —hypersensitivity to drug or class

  • Caution —hepatic or splenic disorders

Maternal Considerations There is no published experience with pentosan polysulfate in pregnancy.
Side effects include hepatotoxicity, diarrhea, N/V, headache, dyspepsia, abdominal pain, dizziness, depression, alopecia, and elevated LFTs.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. Pentosan polysulfate does not appear to cross the human placenta and should pose little risk during pregnancy. Rodent studies are reassuring, revealing no evidence of teratogenicity or IUGR.
Breastfeeding Safety There are no published studies in nursing women. It is unknown whether pentosan polysulfate enters human breast milk. However, its high molecular weight and poor oral bioavailability would seem to preclude its accumulation in a breastfeeding neonate.
Drug Interactions No clinically relevant interactions identified.
References Forestier F, Fischer AM, Daffos F, et al. Thromb Haemost 1986; 56:247-9.
Summary Pregnancy Category: B
Lactation Category: S (likely)

  • Pentosan polysulfate should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

Pentostatin — (Nipent)

International Brand Names

Coforin (Japan); Nipent (Canada, England, France, Germany, Italy, Netherlands, Portugal)

Drug Class Antineoplastics, antimetabolite
Indications Hairy cell leukemia
Mechanism Inhibits adenosine deaminase
Dosage With Qualifiers Hairy cell leukemia—4 mg/m 2 IV qw

  • Contraindications —hypersensitivity to drug or class, concomitant fludarabine use

  • Caution —active infection, renal dysfunction

Maternal Considerations There is no published experience with pentostatin during pregnancy.
Side effects include N/V, arrhythmia, hemorrhage, leukopenia, thrombocytopenia, fatigue, anorexia, diarrhea, headache, rash, bronchitis, fever, chills, hematuria, and somnolence.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether pentostatin crosses the human placenta. The developing mouse allantois is quite sensitive to pentostatin, and interference with allantois development leads to embryo lethality. Late exposure in rodent pregnancy is associated with neural tube, craniofacial, and limb defects.
Breastfeeding Safety There is no published experience during lactation. It is unknown whether pentostatin enters human breast milk. Women should avoid breastfeeding for at least 2 d after receiving pentostatin.
Drug Interactions Enhances the antiviral effects of vidarabine. Combined use may increase the adverse reactions associated with each drug.
Use with fludarabine is not recommended, as it may be associated with an increased risk of fatal pulmonary toxicity.
References Airhart MJ, Robbins CM, Knudsen TB, et al. Teratology 1993; 47:17-27.
Airhart MJ, Robbins CM, Knudsen TB, et al. Teratology 1996; 53:361-73.
Summary Pregnancy Category: D
Lactation Category: NS (possibly)

  • Pentostatin should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

Pentoxifylline — (Ebisanin; Sipental; Techlon; Trental)

International Brand Names

Agapurin (Singapore, Thailand); Artal (Finland); Azupentat (Germany); Carpental S.R. (Korea); Cental (Taiwan); Ceretal (Taiwan); C-Vex (Philippines); Elorgan (Spain); Erytral (Indonesia); Fixoten (Mexico); Flexital (Philippines); Harin (Korea); Harine (Korea); Hemovas (Spain); Ipentol (Taiwan); Kentadin (Mexico); Oxopurin 400 SR (Israel); Penphylline (Taiwan); Pentong (Hong Kong); Pentox (Philippines); Pentoxi (Switzerland); Pentoxifilin (Colombia); Pentoxine (Israel); Perencal (Korea); Perental (Korea); Peridane (Mexico); Pexal (Puerto Rico); Pexol (Peru); Platof (Indonesia); Tarontal (Greece, Indonesia); Torental (Belgium, France); Trenfyl (Indonesia); Trenlin (Hong Kong); Trenlin SR (Singapore); Trental (New Zealand, South Africa); Trepal-400 (Thailand); Vazofen (Philippines)

Drug Class Hematologics; Xanthine derivatives
Indications Claudication
Mechanism Decreases blood viscosity, improves RBC membrane flexibility
Dosage With Qualifiers Claudication—400 mg PO tid with meals

  • Contraindications —hypersensitivity to drug or class, methylxanthine intolerance

  • Caution —recent retinal or cerebral hemorrhage

Maternal Considerations Pentoxifylline and its metabolites improve the flow properties of blood by decreasing viscosity. It also inhibits TNF-α–induced complement C3 synthesis. Pentoxifylline is used with tocopherol to treat IVF patients with a thin endometrium. It also enhances sperm motility prior to IVF or IUI. It has even been used in a preliminary study to treat endometriosis-related infertility. In rodents, long-term use is associated with the development of mammary fibroadenomas. There are no adequate reports or well-controlled studies during pregnancy. Clearance is unaltered by pregnancy.
Side effects include arrhythmia, angina, N/V, diarrhea, dyspepsia, dizziness, headache, insomnia, blurred vision, drowsiness, and agitation.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether pentoxifylline crosses the human placenta. Rodent studies are reassuring, revealing no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically. Embryotoxicity was noted.
Breastfeeding Safety There are no adequate reports or well-controlled studies in nursing women. Pentoxifylline and its metabolites enter human breast milk, achieving near unity with maternal plasma. However, the relative infant dose is estimated to be below 0.5%.
Drug Interactions Although a causal relationship is not established, there are reports of bleeding and/or prolonged PT in patients treated with pentoxifylline with and without anticoagulants or platelet aggregation inhibitors. Patients on coumadin should undergo more frequent monitoring of PTs, whereas patients with other risk factors complicated by hemorrhage (e.g., recent surgery, peptic ulcer) should have periodic tests for bleeding.
Pentoxifylline may increase theophylline and the risk of theophylline toxicity in some patients. Monitor closely for signs of toxicity, and adjust the theophylline dose as appropriate.
References Boiko SS, Zherdev VP, Vikhliaeva EM, Supriaga OM. Eksp Klin Farmakol 1992; 55:52-5.
Creus M, Fabregues F, Carmona F, et al. Hum Reprod 2008; 23:1910-6.
Griveau JF, Lobel B, Laurent MC, et al. Reprod Biomed Online 2006; 12:14-8.
Hoie EB, McGuire TR, Leuschen PM, Zach TL. Biol Pharm Bull 2004; 27:1670-3.
Ledee-Bataille N, Olivennes F, Lefaix JL, et al. Hum Reprod 2002; 17:1249-53.
Terriou P, Hans E, Giorgetti C, et al. J Assist Reprod Genet 2000; 17:194-9.
Witter FR, Smith RV. Am J Obstet Gynecol 1985; 151:1094-7.
Summary Pregnancy Category: C
Lactation Category: S (possibly)

  • Pentoxifylline should be used during pregnancy only if the benefit justifies the potential perinatal risk.

  • There is no published experience during pregnancy except in infertility patients.

Perindopril erbumine — (Aceon)

International Brand Names

Acertil (China, Hong Kong, Korea, Taiwan); Coverene (Argentina); Coversum (Austria, Germany, Switzerland); Coversyl (Belgium, Brazil, Canada, Chile, Colombia, Costa Rica, Denmark, Dominican Republic, Ecuador, El Salvador, England, France, Greece, Guatemala, Honduras, India, Ireland, Italy, Japan, Kuwait, Malaysia, Mexico, Netherlands, Nicaragua, Panama, Paraguay, Philippines, Portugal, South Africa, Spain, Thailand, United Arab Emirates, Venezuela); Perinace (Malaysia); Prexum (Indonesia)

Drug Class ACEI/A2R-antagonists; Antihypertensives
Indications Hypertension, CHF
Mechanism ACE inhibitor
Dosage With Qualifiers Hypertension—begin 4 mg PO qd; max 16 mg/d
CHF—begin 2 mg PO qd
NOTE: Renal dosing; lower dose if on a diuretic.

  • Contraindications —hypersensitivity to drug or class, history of ACEI-induced or idiopathic angioedema

  • Caution —renal dysfunction, renal artery stenosis, severe CHF, collagen vascular disease, volume depletion, hyponatremia, pregnancy

Maternal Considerations There is no published experience with perindopril during pregnancy. The lowest effective dose should be used when it is required during pregnancy for BP control.
Side effects include fetal or neonatal death, angioedema, hypotension, renal failure, hyperkalemia, neutropenia, agranulocytosis, pancreatitis, cough, N/V, musculoskeletal pains, dizziness, fatigue, and elevated BUN/Cr.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether perindopril crosses the human placenta. It does cross the rabbit placenta. Other renin-angiotensin system inhibitors cross the human placenta and, contrary to initially beliefs, may cause fetal cranial hypoplasia, anuria, reversible or irreversible renal failure, death, oligohydramnios, prematurity, IUGR, and PDA beginning with a first-trimester exposure. There is no reason to expect perindopril is different.
Breastfeeding Safety There is no published experience in nursing women. It is unknown whether perindopril enters human breast milk. The experience with other ACE inhibitors suggests it is unlikely to achieve a significant level in breast milk. In the meantime, there are other ACE inhibitors safe for breastfeeding including captopril or enalapril.
Drug Interactions Patients on diuretics, especially those started recently, may occasionally experience an excessive reduction of BP after initiation of perindopril therapy. Hypotension can be minimized by either discontinuing the diuretic or increasing salt intake prior to initiation of perindopril. If diuretics cannot be interrupted, close medical supervision should be provided with the first dose of perindopril, for at least 2 h, and until BP has stabilized for another hour.
Diuretics reduce bioavailability; this is also associated with a decrease in plasma ACE inhibition.
May increase serum potassium because of its potential to decrease aldosterone production. Use of potassium-sparing diuretics (e.g., amiloride, spironolactone, triamterene ), potassium supplements, or other drugs capable of increasing serum potassium (e.g., cyclosporine, heparin, indomethacin ) can increase the risk of hyperkalemia. They should be used cautiously and the serum potassium monitored frequently.
Increased serum lithium and symptoms of lithium toxicity are reported. Caution coupled to frequent monitoring of serum lithium levels is recommended. Use of a diuretic may further increase the risk of lithium toxicity.
Animal data suggest the possibility of an interaction with gentamicin. Use caution if both drugs must be used together.
References Moulin B, Morin JP, Seurin-Toutain P, et al. Int J Tissue React 1990; 12:309-17.
Summary Pregnancy Category: C (first trimester), D (second and third trimesters)
Lactation Category: U

  • Perindopril and other inhibitors of the renin-angiotensin system are potentially teratogenic throughout pregnancy and should be avoided whenever possible.

  • There are alternative agents for which there is more experience regarding use during pregnancy and lactation.

  • When the mother’s disease requires treatment with perindopril, the lowest dose should be used and coupled with close monitoring of the fetus.

Permethrin topical — (Acticin; Elimite; Nix)

International Brand Names

Assy (Argentina); Destolit (Peru); Dronol (Paraguay); Expar Shampoo (Israel); Gamabenceno Plus (Colombia); Gamaderm (Colombia); Infectopedicul (Germany); Klinits (Chile); Loxazol (Netherlands, Switzerland); Lyclear (England, Ireland, South Africa); Lyclear Creme Rinse (Israel); Lyclear Dermal Cream (Israel); Lyclear Scabies Cream (Australia); Mite-X (Israel); Nedax Plus (Brazil); New-Nok (Israel); Nix (Denmark, Finland, France, Italy, Norway, Sweden); Nix Cream (Puerto Rico); Nix Creme Rinse (Canada); Nix Dermal Cream (Canada, Puerto Rico); Nok (Israel); Novo-Herklin 2000 (Mexico); Permicren (Uruguay); Permite (India); Piopel (Honduras, Nicaragua); Pyrifoam (Australia, Philippines); Quellada Creme Rinse (Australia); Quellada Head Lice (New Zealand); Quellada-P (New Zealand); Scabmite (Indonesia); Zehu-Ze (Israel)

Drug Class Antiparasitics; Dermatologics; Scabicides/pediculicides
Indications Scabies
Mechanism Disrupts nerve cell sodium channel currents in parasite
Dosage With Qualifiers Scabies—massage into skin from head to toe, allow to remain 8–14 h before bathing

  • Contraindications —hypersensitivity to drug or class

  • Caution —unknown

Maternal Considerations Permethrin is rapidly metabolized to inactive metabolites that are excreted primarily in the urine. Although the amount of permethrin absorbed after a single application has not been precisely determined, preliminary study suggests it is less than 2% of the amount applied. There are no adequate reports or well-controlled studies in pregnant women. Permethrin improves maternal outcome when used as part of a broad strategy such as insecticide-incorporating nets.
Side effects include burning, numbness, tingling, pruritus, and erythema.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether permethrin crosses the human placenta. Several large case series and prospective studies are reassuring. However, there are grounds for concern as the rates of both acute lymphocytic leukemia and acute myelogenous leukemia were increased in children 0–11 mo (aOR = 2.47 and 7.28, respectively) after first-trimester maternal exposure. Rodent studies are reassuring, revealing no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically.
Breastfeeding Safety There are no adequate reports or well-controlled studies in nursing women. Permethrin enters human breast milk, but the kinetics remain to be elucidated. Considering the route and frequency of use, it is unlikely a maternal clinically relevant systemic concentration will be reached and sustained.
Drug Interactions No clinically relevant interactions identified.
References Bouwman H, Sereda B, Meinhardt HM. Environ Pollut 2006; 144:902-17.
Ferreira JD, Couto AC, Pombo-de-Oliveira MS, et al. Environ Health Perspect 2013; 121:269-75.
Imamura L, Hasegawa H, Kurashina K, et al. Arch Toxicol 2002; 76:392-7.
Judge MR, Kobza-Black A. Br J Dermatol 1995; 132:116-9.
Kennedy D, Hurst V, Konradsdottir E, et al. Am J Perinatol 2005; 22:87–90.
Mytton OT, McGready R, Lee SJ, et al. BJOG 2007; 114:582-7.
Summary Pregnancy Category: B
Lactation Category: S (likely)

  • Permethrin should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

Perphenazine — (Trilifan; Trilafon)

International Brand Names

APO-Perphenazine (Canada, Malaysia); Decentan (Austria, Germany, Spain); Fentazin (England, Ireland); F-Mon (Japan); Leptopsique (Mexico); Peratsin (Finland); Pernamed (Thailand); Pernazine (Thailand); Perphenan (Israel); Perzine-P (Thailand); Porazine (Thailand); Trilafon (Canada, Denmark, Indonesia, Italy, Japan, Netherlands, Norway, Philippines, South Africa, Sweden, Switzerland); Trilifan Retard (France); Trimin (Korea); Triomin (Taiwan)

Drug Class Antiemetics; Antipsychotics; Antivertigo agents; Phenothiazines
Indications Psychosis, severe N/V
Mechanism Unknown; antagonizes D 2 receptors
Dosage With Qualifiers Psychosis—8–16 mg PO bid to qid; max 64 mg/d
Severe N/V—begin 5 mg IM/PO (avoid IV); max 24 mg/d

  • Contraindications —hypersensitivity to drug or class, CNS depression, blood dyscrasias, bone marrow depression, hepatic disease, coma, subcortical damage

  • Caution —unknown

Maternal Considerations Perphenazine is commonly combined with amitriptyline (Triavil, Etrafon) in the United States. It increases circulating prolactin levels in both humans and rodents. There are no well-controlled studies in pregnant women. Maternal concentrations appear to decline with advancing gestation. Some phenothiazines have been associated with a prolongation of the QT interval.
Side effects include cardiac arrest, tachycardia, seizures, hepatotoxicity, hemolytic anemia, agranulocytosis, thrombocytopenia, neuroleptic malignant syndrome, extrapyramidal effects, tardive dyskinesia, sedation, drowsiness, dry mouth, blurred vision, N/V, rash, and anorexia.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether perphenazine crosses the human placenta. However, peroxidative bioactivation of perphenazine by human placental peroxidase occurs and may be one mechanism of the reported toxicity of other phenothiazines. Postnatal behavioral abnormalities are suggested. Withdrawal symptoms and hyperreflexia have been reported in newborns exposed to phenothiazine during pregnancy. Rodent teratogenicity studies apparently have not been conducted.
Breastfeeding Safety There are no well-controlled studies in nursing women. Perphenazine enters human breast milk. However, the relative infant dose is estimated to be less than 0.25%.
Drug Interactions Some 10% of Caucasians have reduced activity of CYP2D6, so-called poor metabolizers. Poor metabolizers have higher plasma concentrations of antipsychotic drugs at usual doses, which may correlate with emergence of side effects. In one study of older adult patients suffering dementia treated with perphenazine, poor metabolizers had significantly greater side effects during the first 10 d of treatment than the extensive metabolizers, after which the groups tended to converge. Prospective phenotyping of older adult patients prior to antipsychotic treatment may identify those at risk for adverse events.
Use of other drugs that inhibit CYP2D6 may acutely increase plasma concentrations of antipsychotics. Among these are TCAs and SSRIs (e.g., fluoxetine, paroxetine, sertraline ). Close monitoring is essential, and dose reduction may become necessary.
References Handal M, Matheson I, Bechensteen AG, Lindemann R. Tidsskr Nor Laegeforen 1995; 115:2539-40.
Olesen OV, Bartels U, Poulsen JH. Am J Psychiatry 1990; 147:1378-9.
Westin AA, Brekke M, Molden E, et al. Clin Pharmacol Ther. 2017 Jun 23.
Yang X, Kulkarni AP. Teratog Carcinog Mutagen 1997; 17:139-51.
Summary Pregnancy Category: C
Lactation Category: S (probably)

  • Perphenazine should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

  • There are alternative agents for which there is more experience regarding use during pregnancy and lactation.

Phenazopyridine — (Azo-Standard; Eridium; Geridium; Phenazodine; Pyridiate; Pyridium; Ro-Pyridine; Urodine; Urodol; Uropyridine; Viridium)

International Brand Names

Anazo (Thailand); Azo Cefasabal (Peru); Azomir (Philippines); Azopiridin (Peru); Cistalgina (Argentina); Nalixone (Mexico); Phenazo (Canada); Phendiridine (Thailand); Pirimir (Mexico); Pyridium (Brazil, Canada, Chile, Ecuador, Hong Kong, India, Indonesia, Peru, Uruguay, Venezuela); Pyronium (Belgium); Sedural (Israel); Tiotal (Paraguay); Urogen (Taiwan); Urogesic (Singapore); Urohman (Japan); Uroprin (Taiwan); Uropyridin (Japan); Uroxacin (Colombia)

Drug Class Analgesics, non-narcotic; GU agents
Indications Dysuria
Mechanism Unknown
Dosage With Qualifiers Dysuria—100–200 mg PO tid pc × 2 d
NOTE: Turns urine red/orange; may be combined with sulfamethoxazole (Azo-Gantanol) or sulfisoxazole (Azo-Gantrisin; Azo-Sulfisoxazole; Azo-Truxazole; Sul-Azo).

  • Contraindications —hypersensitivity to drug or class, renal insufficiency, uremia, hepatitis, glomerulonephritis, pyelonephritis during pregnancy

  • Caution —unknown

Maternal Considerations Phenazopyridine has a topical analgesic effect on urinary tract mucosa, helping to relieve pain, burning, urgency, and frequency. There are no adequate reports or well-controlled studies in pregnant women.
Side effects include anemia, headache, N/V, dyspepsia, pruritus, and stained contact lenses.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. One study indicated that phenazopyridine crosses the human placenta, although the kinetics remain to be elucidated. It is also found in the amniotic cavity, and false diagnosis of premature rupture of the membranes has been attributed to it. The Collaborative Perinatal Project monitored 219 women with first-trimester exposure and 1109 women with exposure to phenazopyridine at any time during pregnancy. There was no increase in the rates of major malformations or any other adverse effects. Rodent studies are reassuring, revealing no evidence of teratogenicity or IUGR despite the use of doses higher than those used clinically.
Breastfeeding Safety There are no adequate reports or well-controlled studies in nursing women. It is unknown whether phenazopyridine enters human breast milk. However, it is generally considered compatible with breastfeeding based on long clinical experience.
Drug Interactions No clinically relevant interactions identified.
References Heinonen OP, Slone D, Shapiro S. Birth defects and drugs in pregnancy. Littleton, MA: Publishing Sciences Group 1977; 297–313.
Ireland KE, Rodriguez EI, Acosta OM, Ramsey PS. Obstet Gynecol 2017; 129:1040-5.
Meyer BA, Gonik B, Creasy RK. Am J Perinatol 1991; 8:297-9.
Summary Pregnancy Category: B
Lactation Category: S

  • Phenazopyridine has been used for decades during pregnancy and lactation.

  • Though there is little objective study, it is generally considered safe for listed indications.

Phendimetrazine — (Adipost; Anorex; Appecon; Bontril; Cam-Metrazine; Dital; Melfiat; Metra; Obalan; Obezine; P.D.M.; Phenazine; Phendiet; Phendimetrazine Bitartrate; Plegine; Prelu-2; PT 105; Statobex; X-Trozine)

International Brand Names

Furing (Korea); Obesan-X (South Africa)

Drug Class Anorexiants; CNS stimulants
Indications Obesity
Mechanism CNS stimulant
Dosage With Qualifiers Obesity—35 mg PO bid or tid; individualize to the lowest effective dose
NOTE: For short-term use only coupled to calorie restriction; tolerance occurs within weeks.

  • Contraindications —hypersensitivity to drug or class, substance abuse, advanced arteriosclerosis, symptomatic CV disease, moderate or severe hypertension, hyperthyroidism, glaucoma, ingestion of other CNS stimulants, agitation

  • Caution —mild hypertension, diabetes mellitus

Maternal Considerations Phendimetrazine is a phenylalkylamine sympathomimetic with pharmacologic activity similar to amphetamine. Obese adult patients given dietary instruction and treated with “anorectic” drugs lost a fraction of a pound more during short-term trials compared with those treated with placebo and diet. Addiction is a risk. There is no published experience with phendimetrazine in pregnancy and no indications for its use.
Side effects include restlessness, insomnia, agitation, flushing, tremor, sweating, dizziness, headache, psychosis, blurred vision, tachycardia, hypertension, dry mouth, nausea, diarrhea, constipation, stomach pain, urinary frequency, dysuria, and libido change.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether phendimetrazine crosses the human placenta. Similar compounds do. Rodent teratogenicity studies have apparently not been performed.
Breastfeeding Safety There are no published studies in nursing women. It is unknown whether phendimetrazine enters human breast milk.
Drug Interactions May result in a hypertensive crisis when used within 14 d of an MAOI.
Caution is indicated if used with other CNS depressants, as the combination may be additive.
References There is no published experience in pregnancy or during lactation.
Summary Pregnancy Category: C
Lactation Category: U

  • There are no indications for the use of phendimetrazine during pregnancy and lactation.

  • Phendimetrazine is of limited value for the treatment of obesity in nonpregnant women.

Phenelzine — (Nardil)

International Brand Names

Nardelzine (Belgium, Spain); Nardil (Australia, Canada, England, Ireland)

Drug Class Antidepressants; MAOIs
Indications Depression, bulimia
Mechanism Inhibits MAO
Dosage With Qualifiers Depression—15 mg PO tid; response may take at least 4 w
Bulimia—begin 15 mg PO tid; max 30 mg PO tid
NOTE: Wait > 4 w after stopping an SSRI before initiating.

  • Contraindications —hypersensitivity to drug or class, CHF, hypertension, pheochromocytoma, hepatic disease, general anesthesia or cocaine use within 10 d, bupropion use

  • Caution —unknown

Maternal Considerations Depression is common during and after pregnancy, but it typically goes unrecognized. Pregnancy is not a reason a priori to discontinue psychotropic drugs. Phenelzine is often effective in treating depression characterized as atypical, nonendogenous, or neurotic. These patients frequently have anxiety and depression mixed with phobic or hypochondriacal features. There are no adequate reports or well-controlled studies of phenelzine in pregnant women. Most publications consist of case reports or small series. Many drugs interact with MAOIs. Well-documented and potentially fatal interactions between MAOIs and opioids, notably meperidine, require that labor analgesia be well planned in advance. Pressor agents should be avoided as even indirect-acting drugs can produce severe hypertension.
Side effects include hypertensive crisis, intracranial hemorrhage, seizures, hypermetabolic syndrome, hypomania, respiratory or CNS depression, coma, leukopenia, SLE-like syndrome, headache, dizziness, weakness, tremor, constipation, dry mouth, dyspepsia, elevated LFTs, weight gain, orthostatic hypotension, hyperreflexia, nystagmus, and edema.
Fetal Considerations There are no adequate reports or well-controlled studies in human fetuses. It is unknown whether phenelzine crosses the human placenta. As for most psychotropic drugs, monotherapy and the smallest effective quantity given in divided doses may reduce risk by minimizing the systemic peaks. Rodent teratogenicity studies have apparently not been performed.
Breastfeeding Safety There is no published experience in nursing women. It is unknown whether phenelzine enters human breast milk.
Drug Interactions Nonselective MAOIs may cause serious, sometimes fatal, reactions if combined with serotonergic agents (e.g., citalopram, dexfenfluramine, fluoxetine, fluvoxamine, paroxetine, sertraline, venlafaxine ), so co-administration should be avoided.
References Gracious BL, Wisner KL. Depress Anxiety 1997; 6:124-8.
Pavy TJ, Kliffer AP, Douglas MJ. Can J Anaesth 1995; 42:618-20.
Summary Pregnancy Category: C
Lactation Category: U

  • Phenelzine should be used during pregnancy and lactation only if the benefit justifies the potential perinatal risk.

Phenobarbital — (Barbita; Dormiral; Luminaletten; Luminal Sodium; Phenobarbital Sodium; Phenobarbitone; Sedofen; Solfoton)

You're Reading a Preview

Become a Clinical Tree membership for Full access and enjoy Unlimited articles

Become membership

If you are a member. Log in here

Related Posts