Betaxolol Tablets

Generic name: betaxolol hydrochloride tablet
Dosage form: tablet, coated
Drug class:Cardioselective beta blockers

Medically reviewed by Drugs.com. Last updated on Nov 1, 2020.

DESCRIPTION:

Betaxolol hydrochloride is a ß 1-selective (cardioselective) adrenergic receptor blocking agent available as 10-mg and 20-mg tablets for oral administration. Betaxolol hydrochloride is chemically described as 2-propanol, 1- [4-[2-(cyclopropylmethoxy) ethyl] phenoxy]-3-[(1-methylethyl) amino]-, hydrochloride, (±)-. It has the following chemical structure:

Each tablet for oral administration contains 10 mg or 20 mg of betaxolol hydrochloride equivalent to 8.94 mg or 17.88 mg of betaxolol respectively. In addition, each tablet contains the following inactive ingredients, carnauba wax, hypromellose, anhydrous lactose, microcrystalline cellulose, polyethylene glycol, polysorbate 80, pregelatinized starch, sodium starch glycolate, stearic acid and titanium dioxide.

Betaxolol hydrochloride is a water-soluble white crystalline powder with a molecular formula of C 18H 29NO 3•HCl and a molecular weight of 343.9. It is freely soluble in water, ethanol, chloroform, and methanol, and has a pKa of 9.4.

CLINICAL PHARMACOLOGY:

Betaxolol is a ß 1-selective (cardioselective) adrenergic receptor blocking agent that has weak membrane-stabilizing activity and no intrinsic sympathomimetic (partial agonist) activity. The preferential effect on ß 1 receptors is not absolute, however, and some inhibitory effects on ß 2 receptors (found chiefly in the bronchial and vascular musculature) can be expected at higher doses.

Pharmacokinetics and Metabolism: In man, absorption of an oral dose is complete. There is a small and consistent first-pass effect resulting in an absolute bioavailability of 89% ± 5% that is unaffected by the concomitant ingestion of food or alcohol. Mean peak blood concentrations of 21.6 ng/ml (range 16.3 to 27.9 ng/ml) are reached between 1.5 and 6 (mean about 3) hours after a single oral dose, in healthy volunteers, of 10 mg of betaxolol. Peak concentrations for 20-mg and 40-mg doses are 2 and 4 times that of a 10-mg dose and have been shown to be linear over the dose ran...