Phenoxybenzamine

Indications

INDICATIONS AND USAGE Phenoxybenzamine Hydrochloride Capsule, USP is 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.

Dosage and administration (summary)

DOSAGE AND ADMINISTRATION The dosage should be adjusted to fit the needs of each patient. Small initial doses should be slowly increased until the desired effect is obtained or the side effects from blockade become troublesome. After each increase, the patient should be observed on that level before instituting another increase. The dosage should be carried to a point where symptomatic relief and/or objective improvement are obtained, but not so high that the side effects from blockade become troublesome. Initially, 10 mg of phenoxybenzamine hydrochloride twice a day.

Contraindications

CONTRAINDICATIONS Conditions where a fall in blood pressure may be undesirable; hypersensitivity to the drug or any of its components.

Warnings and precautions

WARNING Phenoxybenzamine hydrochloride-induced alpha -adrenergic blockade leaves beta -adrenergic receptors unopposed. Compounds that stimulate both types of receptors may, therefore, produce an exaggerated hypotensive response and tachycardia.

Pregnancy

Pregnancy Teratogenic Effects Adequate reproductive studies in animals have not been performed with phenoxybenzamine hydrochloride. It is also not known whether phenoxybenzamine hydrochloride can cause fetal harm when administered to a pregnant woman.

Storage and supply

HOW SUPPLIED Phenoxybenzamine Hydrochloride Capsules USP, 10 mg: are supplied as transparent red/transparent red size 3 hard gelatin capsule shells, imprinted with ‘C118’ on cap and ‘10’ on body with white ink, filled with white to off white powder, in bottles of 100 (NDC 16571-874-01)

Source: Phenoxybenzamine Hydrochloride (Phenoxybenzamine Hydrochloride) — US FDA prescribing information, 2026-06-18, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.