Phenylephrine (Neo-Synephrine)

Prescribed mainly as nasal decongestant or ophthalmically for treatment of mydriasis, capillary decongestion.

Reliable vasopressor in treatment of hypotension.

Used in obstetric anesthesia for hypotension after spinal. More effective as a prophylactic infusion than bolus doses.

Prolongs local anesthetic duration in regional anesthesia.

Available as parenteral IM/IV and various ophthalmic and/or nasal preparations.

Risk of Htn increases left heart work; may precipitate myocardial ischemia, MI.

Infusions to augment systolic BP incidence of myocardial ischemia in pts undergoing carotid endarterectomy.

Increased pulm vascular resistance, right heart work.

Bradycardia may occur (usually not severe) related to baroreceptor reflex.

Decreased renal, splanchnic blood flow.

Systemic absorption of topical preparations may cause Htn, headache, tremulousness, myocardial ischemia.

Increase preload, afterload may worsen LV failure in pts with LV dysfunction.

Raised PA pressures may worsen RV dysfunction.

May decrease renal blood flow.