Overview
11 DESCRIPTION Metoprolol tartrate tablets, USP contain metoprolol tartrate, a selective beta 1 -adrenoreceptor blocking agent. Metoprolol tartrate is (±)-1-(isopropylamino)-3-[ p -(2-methoxyethyl)phenoxy]-2-propanol (2:1) dextro -tartrate salt, and its structural formula is Metoprolol tartrate USP is a white, practically odorless, crystalline powder with a molecular weight of 684.82.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action 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.
Indications
- 1 INDICATIONS AND USAGE Metoprolol tartrate tablets are 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. ( 1.1 ) Angina Pectoris. ( 1.2 ) 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. ( 1.3 ) 1.
Common Doses
- 100 mg
- 450 mg
- 400 mg
- 50 mg
Dosage
2 DOSAGE AND ADMINISTRATION Administer once daily with food or after a meal. Titrate at weekly or longer intervals as needed and tolerated. ( 2 ) Hypertension: Recommended starting dosage is 100 mg daily, in single or divided doses. ( 2.1 ) Angina Pectoris: Recommended starting dosage is 100 mg daily, given as two divided doses. ( 2.2 ) Myocardial Infarction: The starting dosage depends upon tolerance of intravenous metoprolol, see full prescribing information. ( 2.3 ) 2.1 Hypertension Individualize the dosage of metoprolol tartrate tablets.
Contraindications
- 4 CONTRAINDICATIONS Metoprolol tartrate tablets are contraindicated in severe bradycardia, second- or third-degree heart block, cardiogenic shock, systolic blood pressure
Side Effects
- 6 ADVERSE REACTIONS The following adverse reactions are described elsewhere in labeling: Worsening angina or myocardial infarction [see Warnings and Precautions (5) ] Worsening heart failure [see Warnings and Precautions (5) ]. Worsening AV block [see Contraindications (4) ]. Most common adverse reactions: tiredness, dizziness, depression, shortness of breath, bradycardia, hypotension, diarrhea, pruritus, rash. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Rising Pharma Holdings, Inc. at 1-844-874-7464 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.
Interactions
- 7 DRUG INTERACTIONS Catecholamine-depleting drugs may have an additive effect when given with beta-blocking agents. ( 7.1 ) Patients may be unresponsive to the usual doses of epinephrine used to treat allergic reaction. ( 7.2 ) CYP2D6 Inhibitors are likely to increase metoprolol concentration. ( 7.3 ) Concomitant use of glycosides, clonidine, and diltiazem and verapamil with beta-blockers can increase the risk of bradycardia. ( 7.4 ) Beta-blockers including metoprolol, may exacerbate the rebound hypertension that can follow the withdrawal of clonidine. ( 7.4 ) 7.