ABSTRACT

Metoprolol is a cardioselective competitive β1-adrenergic receptor antagonist with antihypertensive properties. This agent antagonizes β1-adrenergic receptors in the myocardium, thereby reducing the rate and force of myocardial contraction, leading to a reduction in cardiac output. In pharmaceutical products, metoprolol is most often employed as metoprolol succinate or as metoprolol tartrate. A group of 28 patients was treated with metoprolol eye drops 1% 3-4 times daily or metoprolol 3% or 4% two to three times a day for glaucoma. Of 7 patients sensitized to alprenolol, 2 (28%) reacted to metoprolol. Three patients sensitized to metoprolol also had positive skin tests to propranolol 1% water, practolol 20% water, and timolol 0.5% water, one each.