Amlodipine + Atenolol

Oral
Chronic stable angina, Hypertension

Per tablet contains atenolol 25 mg and amlodipine (besylate) 5 mg: Initiate with 1 tablet daily.

Hypotension, sinus bradycardia, 2nd & 3rd degrees of heart block, cardiogenic shock, overt congestive failure, poor LV function, hypersensitivity to either component, pregnancy.

Excessive fall of BP may occur in elderly patients. Caution in patients with COPD, thyrotoxicosis, congestive failure, vasospastic angina, hepatic & renal impairment. Caution in diabetic patients as beta-blockers may mask tachycardia occurring with hypoglycaemia. Withdrawal should be gradual. Lactation. Safety and efficacy have not been established in children. Not to be used in untreated phaeochromocytoma.

Headache, hypotension, dizziness, breathlessness, fatigue, muscle cramps, bradycardia, palpitations, flushing, oedema, dyspnoea, dyspepsia, cold extremities. Drowsiness, chestpain & impotence rarely. Hypersensitivity reactions.

Overdosage may cause hypotension and less commonly, congestive cardiac failure. Unabsorbed drug may be removed by gastric lavage or use of activated charcoal. Symptomatic treatment may be administered.

Additive effect when used with catecholamine depleting drugs; monitor for hypotension and/or marked bradycardia. If used with clonidine, clonidine withdrawal should occur a few days after withdrawal of the beta-blocker to prevent rebound hypertension; if replacing clonidine by beta-blocker, beta-blocker should be introduced only after clonidine administration has stopped for several days. Concurrent use with prostaglandin synthase inhibiting drugs (e.g. indomethacin) may reduce the hypotensive effects of beta-blockers.

Description:
Mechanism of Action: Atenolol is a cardioselective beta blocker. Amlodipine is a dihydropyridine calcium-channel blocker that blocks the transmembrane influx of calcium ions into vascular smooth muscle and cardiac muscle. Combination of the two drugs results in additive antihypertensive action.
Pharmacokinetics:
Absorption: Amlodipine: Plasma levels peak 6-12 hr after oral admin; absolute bioavailability is estimated to be 64-90%. Atenolol: Absorption is rapid and consistent but incomplete; about 50% of an oral dose is absorbed in the GI tract; plasma levels peak 2-4 hr after oral admin.
Distribution: Amlodipine: 93% bound to plasma proteins. Atenolol: 6-16% bound to plasma proteins.
Metabolism: Amlodipine: About 90% converted to inactive metabolites hepatically. Atenolol: Little or no hepatic metabolism.
Excretion: Amlodipine: 10% of parent compound and 60% of the metabolites are removed in the urine; elimination from the plasma is biphasic with terminal half-life of about 30-50 hr. Atenolol: 50% of the oral dose is removed unchanged in the faeces; absorbed drug is removed mainly via renal elimination; half-life is about 6-7 hr.

Anti-Anginal Drugs / Beta-Blockers / Calcium Antagonists