Product Description 
Atenolol is a competitive,ß-1 selective adrenergic antagonist, similar to metoprolol. ß-adrenergic antagonists counter the effect of sympathomimetic neurotransmitters (i.e., catecholamines) by competing for receptor sites. Similar to metoprolol, it, in low doses, selectively blocks sympathetic stimulation mediated by ß-adrenergic receptors in the heart and vascular smooth muscle. It antagonizes ß1 receptors at doses 50 to 100 times less than those required to block ß2 receptors. This cardioselectivty is more pronounced at low doses and is lost at high doses. It lowers the blood pressure in hypertension and slows the heart rate.