Metoprolol

1 IND ICATIONS AND USAGE LOPRESSOR is a beta-adrenergic blocker indicated for the treatment of: Hypertension, to lower blood pressure. Lowering blood pressure reduces the risk of fatal and non-fatal cardiovascular events, primarily strokes and myocardial infarctions. Angina Pectoris. Myocardial Infarction, to reduce the risk of cardiovascular mortality when used in conjunction with intravenous metoprolol therapy in patients with definite or suspected acute myocardial infarction in hemodynamically stable patients.

Metoprolol is a beta 1 -selective (cardioselective) adrenergic receptor blocking agent. This preferential effect is not absolute, however, and at higher plasma concentrations, metoprolol also inhibits beta 2 -adrenoreceptors, chiefly located in the bronchial and vascular musculature. Metoprolol has no intrinsic sympathomimetic activity, and membrane-stabilizing activity is detectable only at plasma concentrations much greater than required for beta-blockade. Animal and human experiments indicate that metoprolol slows the sinus rate and decreases AV nodal conduction. The relative beta 1 -selectivity of metoprolol has been confirmed by the following: In normal subjects, metoprolol is unable to reverse the beta 2 -mediated vasodilating effects of epinephrine. This contrasts with the effect of nonselective beta-blockers, which completely reverse the vasodilating effects of epinephrine.

Administer once daily with food or after a meal. Titrate at weekly or longer intervals as needed and tolerated. Hypertension: Recommended starting dosage is 100 mg daily, in single or divided doses. Angina Pectoris: Recommended starting dosage is 100 mg daily, given as two divided doses. Myocardial Infarction: The starting dosage depends upon tolerance of intravenous metoprolol, see full prescribing information.

LOPRESSOR is contraindicated in severe bradycardia, second- or third-degree heart block, cardiogenic shock, systolic blood pressure <100, decompensated heart failure, sick sinus syndrome (unless a permanent pacemaker is in place), and in patients who are hypersensitive to any component of this product. Known hypersensitivity to product components. Severe bradycardia: Greater than first degree heart block, or sick sinus syndrome without a pacemaker. Cardiogenic shock or decompensated heart failure.

Abrupt cessation may exacerbate myocardial ischemia. Heart Failure: Worsening cardiac failure may occur. Bronchospastic Disease: Avoid beta-blockers. Pheochromocytoma: Initiate therapy with an alpha blocker. Major Surgery: Avoid initiation of high-dose extended-release metoprolol in patients undergoing non-cardiac surgery. Do not routinely withdraw chronic beta-blocker therapy prior to surgery. Diabetes: May mask symptoms of hypoglycemia. Thyrotoxicosis: Abrupt withdrawal in patients with thyrotoxicosis might precipitate a thyroid storm. Peripheral Vascular Disease: Can aggravate symptoms of arterial insufficiency.

The following adverse reactions are described elsewhere in labeling: Worsening angina or myocardial infarction Worsening heart failure. Worsening AV block. Most common adverse reactions: tiredness, dizziness, depression, shortness of breath, bradycardia, hypotension, diarrhea, pruritus, rash.

Catecholamine-depleting drugs may have an additive effect when given with beta-blocking agents. Patients may be unresponsive to the usual doses of epinephrine used to treat allergic reaction. CYP2D6 Inhibitors are likely to increase metoprolol concentration. Concomitant use of glycosides, clonidine, and diltiazem and verapamil with beta-blockers can increase the risk of bradycardia. Beta-blockers including metoprolol, may exacerbate the rebound hypertension that can follow the withdrawal of clonidine.

Store at 77°F (25°C), excursions permitted to 59° to 86°F (15° to 30°C). Protect from moisture and heat.