Description : A cardioselective beta-adrenergic blocker possessing properties and potency similar to propranolol, but without a negative inotropic effect. dose: Adult: PO- Angina pectoris- HTN- 50-100 mg once daily. Migraine prophylaxis 50-100 mg/day. Indication : For the management of hypertention and long-term management of patients with angina pectoris Mechanism of action: Like metoprolol, atenolol competes with sympathomimetic neurotransmitters such as catecholamines for binding at beta(1)-adrenergic receptors in the heart and vascular smooth muscle, inhibiting sympathetic stimulation. This results in a reduction in resting heart rate, cardiac output, systolic and diastolic blood pressure, and reflex orthostatic hypotension. Higher doses of atenolol also competitively block beta(2)-adrenergic responses in the bronchial and vascular smooth muscles.