PROPRANOLOL HYDROCHLORIDE- propranolol hydrochloride tablet
Impax Generics
DESCRIPTION
Propranolol hydrochloride, USP is a synthetic beta-adrenergic receptor blocking agent chemically described as 2-Propanol, 1-[(1-methylethyl)amino]-3-(1-naphthalenyloxy)-, hydrochloride,(�)-
C16 H21 NO2 �HCl M.W. 295.80
Propranolol hydrochloride, USP is a stable, white, crystalline solid which is readily soluble in water and in ethanol.
Propranolol Hydrochloride Tablets USP are available as tablets for oral administration containing 60 mg of propranolol hydrochloride, USP. Propranolol Hydrochloride Tablets USP also contain lactose anhydrous, magnesium stearate, microcrystalline cellulose, and sodium starch glycolate. Color additives include FD&C Yellow no. 6 aluminum lake (10 mg and 80 mg), D&C Yellow no. 10 aluminum lake (10 mg, 40 mg, and 80 mg), FD&C Blue no. 1 aluminum lake (20 mg and 40 mg) and FD&C Red no. 40 aluminum lake (60 mg).
CLINICAL PHARMACOLOGY
General
Propranolol is a nonselective beta-adrenergic receptor blocking agent possessing no other autonomic nervous system activity. It specifically competes with beta-adrenergic receptor agonist agents for available receptor sites. When access to beta-receptor sites is blocked by propranolol, the chronotropic, inotropic, and vasodilator responses to beta-adrenergic stimulation are decreased proportionately. At dosages greater than required for beta-blockade, propranolol also exerts a quinidine-like or anesthetic-like membrane action, which affects the cardiac action potential. The significance of the membrane action in the treatment of arrhythmias is uncertain.
Mechanism of Action
The mechanism of the antihypertensive effect of propranolol has not been established. Factors that may contribute to the antihypertensive action include: (1) decreased cardiac output, (2) inhibition of renin release by the kidneys, and (3) diminution of tonic sympathetic nerve outflow from vasomotor centers in the brain. Although total peripheral resistance may increase initially, it readjusts to or below the pretreatment level with chronic use of propranolol. Effects of propranolol on plasma volume appear to be minor and somewhat variable.