General information Glucagon, which is produced in the alpha cells of the islets of Langerhans, is used in type 1 diabetes mellitus to stimulate glucose output from the liver during hypoglycemia (1 mg subcutaneously, repeated once or twice) when glucose cannot be given intravenously. In some countries it is often used by personnel, such as family members, who are not medically qualified, as the first action…

General information Glaucine is a non-narcotic antitussive agent with anti-inflammatory action but little analgesic action [ ]. The D-isomer of glaucine is an alkaloid from Glaucium flavum Crantz , a species of Papaveraceae [ ]. It is as effective as codeine but has a shorter duration of action [ ]. Although glaucine prevents histamine-induced bronchoconstriction in guinea-pigs it does not have a similar action in humans…

General information Glatiramer acetate (Copaxone, also known as co-polymer 1 or cop-1) is an immunomodulatory drug that consists of a pool of synthetic peptides composed of random sequences of four amino acids, l -alanine, l -lysine, l -glutamic acid, and l -tyrosine. Its composition is based on the amino acid structure of myelin basic protein. It has been used to treat relapsing multiple sclerosis. Glatiramer acetate…

See also Floctafenine . General information Glafenine, an anthranilic acid derivative, has been withdrawn in much of the world [ ]. Until 1991 it was sold in about 70 countries (although never marketed or accepted in others), despite a long history of severe reactions (particularly anaphylaxis, fatal hepatotoxicity, and nephrotoxicity, even with normal doses). As late as 1989 the EC Committee on Proprietary Medicinal Products (CPMP)…

General information “Ginseng” is an ambiguous vernacular term, which can refer to Panax species such as Panax ginseng (Asian ginseng) and Panax quinquefolius (American ginseng), Eleutherococcus senticosus (Siberian ginseng), Pfaffia paniculata (Brazilian ginseng), or unidentified material (for example Rumanian ginseng). The genera in the family of Araliaceae (qv) include aralia, ginseng, and ivy. Asian ginseng ( Panax ginseng ) contains a wide variety of flavonoids, saponins,…

General information The family of Ginkgoaceae contains the single genus, Ginkgo, and a single species, Ginkgo . Ginkgo Ginkgo (maidenhair tree, silver apricot) contains ginkgolides, which inhibit platelet-activating factor, reducing aggregability; this may contribute to bleeding disorders in patients taking Ginkgo . Ginkgo has small beneficial effects in patients with intermittent claudication [ ] and dementias [ , ]. Extracts from the leaves of Ginkgo are…

General information Germanium is a metallic element (symbol Ge; atomic no. 32) that is found as the sulfide in the mineral argyrodite. In several countries, organic or inorganic germanium has acquired a remarkable reputation in self-medication as a widely useful prophylactic and therapeutic agent, but with little scientific evidence to support it. Some germanium compounds, particularly spirogermanium, do have certain immunoregulatory activities, but germanium itself does…

General information The genera in the family of Gentianaceae ( Table 1 ) include centaury and various types of gentian. Table 1 Genera of Gentianaceae Bartonia (screwstem) Centaurium (centaury) Cicendia (cicendia) Enicostema (whitehead) Eustoma (prairie gentian) Frasera (green gentian) Gentiana (gentian) Gentianella (dwarf gentian) Gentianopsis (fringed gentian) Halenia (spurred gentian) Lisianthius (lisianthius) Lomatogonium (lomatogonium) Obolaria (obolaria) Sabatia (rose gentian) Schultesia (wingcup) Swertia (felwort) Voyria (ghostplant) You’re…

See also Aminoglycoside antibiotics General information Gentamicin is well established for the treatment of several bacterial infections, especially those caused by Gram-negative bacteria, including Pseudomonas aeruginosa , Klebsiella species, and Serratia marcescens . In adults, it is usually given in daily doses of 240–360 mg. Drug studies Observational studies In 17 patients with suspected postoperative endophthalmitis who were given intravitreal vancomycin 0.2 mg and gentamicin 0.05…

See also Antifungal azoles [for systemic use] General information Genaconazole is an N-substituted triazole with a wide antifungal spectrum. Its absorption is slow, with peak concentrations 2–4 hours after a single dose and mean peak concentrations markedly higher after 16 days of administration. The half-life is about 90–100 hours [ ]. It has high tissue penetration, including the CNS, and good broad-spectrum antifungal activity. However, it…

See also Monoclonal antibodies General information Gemtuzumab ozogamicin (Mylotarg) consists of a humanized anti-CD33 monoclonal antibody conjugated to the cytotoxic enediyne antibiotic calicheamicin. It has been used to treat a subset of patients with acute myeloid leukemia in association with topotecan + cytarabine. Its most common adverse effects and reactions are myelosuppression, increased hepatic enzyme activity, infections, fever and chills, bleeding, nausea and vomiting, and dyspnea.…

See also Fluoroquinolones General information Gemifloxacin is a fluoroquinolone that has enhanced affinity for topoisomerase. Compared with other fluoroquinolones, gemifloxacin was the most potent against penicillin-intermediate and penicillin-resistant pneumococci, methicillin-susceptible and methicillin-resistant Staphylococcus epidermidis isolates, and coagulase-negative staphylococci [ , ]. It has excellent activity against Haemophilus influenzae and Moraxella catarrhalis and is unaffected by beta-lactamases. It is generally two-fold less active than ciprofloxacin against most…

See also Prostaglandins General information Gemeprost is an analogue of PGE 2 . Vaginal gemeprost is effective in inducing first and second trimester abortion and in cervical priming before vacuum aspiration. Pyrexia, vomiting, and diarrhea were experienced in 20% of patients [ ]. Organs and systems You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you…

See also Cytotoxic and immunosuppressant drugs General information Gemcitabine is an S-phase-specific pyrimidine nucleoside analogue of deoxycytidine (2',2'-difluorodeoxycytidine) that is structurally similar to cytosine arabinoside. It has been used to treat metastatic urothelial carcinoma of the bladder, pancreatic cancer, and some other solid tumors. Drug studies Observational studies In a retrospective study of patients with non-small cell lung cancers who received gemcitabine 1000 mg/m 2 on…

General information Gefitinib is an anilinoquinazoline derivative, the first agent to have been introduced as a potent inhibitor of EGFR tyrosine kinase for the treatment of advanced non-small-cell lung cancer refractory or resistant to cytotoxic chemotherapy. Case series have shown significant radiographic regression and improvement of symptoms. A history of never smoking cigarettes and bronchoalveolar histology are significant predictors of a radiographic response to gefitinib. In…

See also Fluoroquinolones General information Gatifloxacin is an 8-methoxyfluoroquinolone with enhanced activity against Gram-positive, atypical agents, and some anerobes, and broad-spectrum activity against Gram-negative bacteria [ ]. It is bactericidal and produces a post-antibiotic effect in Gram-positive and Gram-negative bacteria. Gatifloxacin is well absorbed from the gastrointestinal tract (oral availability almost 100%), and concomitant administration of a continental breakfast, 1050 kcal, had no effect on its…

See also Fluoroquinolones General information Garenoxacin (T-3811ME, BMS-284756) is a des-F(6) quinolone that is effective in vitro against a wide range of clinically important pathogens, including Gram-positive and Gram-negative aerobes and anaerobes [ ]. Drug studies 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

General information Ganciclovir (dihydroxypropoxymethylguanine) is a nucleoside analogue with antiviral activity in vitro against herpesviruses. Intracellular phosphorylation of ganciclovir to its triphosphate derivative, which acts as a competitive inhibitor of deoxyguanosine triphosphate, leads to the inhibition of viral DNA synthesis. Because its toxicity profile is more favorable than those of foscarnet and cidofovir, it should be considered first-line treatment of life-threatening or sight-threatening cytomegalovirus (CMV) infections…

General information Sodium gammahydroxybutyrate (GHB or sodium oxybate) is an endogenous compound, a precursor of GABA, which increases the release of dopamine and acetylcholine in the brain. It was first synthesized in 1960 as a potential anesthetic, and was popular in the late 1980s and early 1990s as a dietary supplement (as a replacement for l -tryptophan after it had been recalled from the market), an…

General information Gallium is a metallic element (symbol Ga; atomic no. 31) that has been used in the form of a radiopharmaceutical ( 67 Ga as the citrate) in diagnostic imaging of cancers, inflammation, and infection [ ]. The mechanisms of the therapeutic activity of gallium have been reviewed [ ]. Gallium nitrate has been used as a therapeutic agent in certain malignancies [ ], since…