PHENOXYBENZAMINE HYDROCHLORIDE- phenoxybenzamine hydrochloride capsule
Roxane Laboratories, Inc.
Rx only
DESCRIPTION
Each Phenoxybenzamine Hydrochloride Capsule USP, with red cap and body, is imprinted with �54 036?, and contains 10 mg of phenoxybenzamine hydrochloride USP. Inactive ingredients consist of anhydrous lactose, black monogramming ink, colloidal silicon dioxide, FD&C Red No. 40, gelatin, purified water, sodium lauryl sulfate, and titanium dioxide. The black monogramming ink contains ammonium hydroxide, iron oxide black, isopropyl alcohol, N-butyl alcohol, propylene glycol, and shellac.
Phenoxybenzamine is N-(2-Chloroethyl)-N-(1-methyl-2-phenoxyethyl)benzylamine hydrochloride:
Phenoxybenzamine hydrochloride is a colorless, crystalline powder with a molecular weight of 340.3, which melts between 136� and 141�C. It is soluble in alcohol and chloroform; insoluble in ether and water.
CLINICAL PHARMACOLOGY
Phenoxybenzamine hydrochloride is a long-acting, adrenergic, alpha -receptor blocking agent, which can produce and maintain �chemical sympathectomy" by oral administration. It increases blood flow to the skin, mucosa and abdominal viscera, and lowers both supine and erect blood pressures. It has no effect on the parasympathetic system.
Twenty to 30 percent of orally administered phenoxybenzamine appears to be absorbed in the active form.1
The half-life of orally administered phenoxybenzamine hydrochloride is not known; however, the half-life of intravenously administered drug is approximately 24 hours. Demonstrable effects with intravenous administration persist for at least 3 to 4 days, and the effects of daily administration are cumulative for nearly a week.1
INDICATIONS AND USAGE
Phenoxybenzamine Hydrochloride Capsules USP are indicated in the treatment of pheochromocytoma, to control episodes of hypertension and sweating. If tachycardia is excessive, it may be necessary to use a beta -blocking agent concomitantly.