Indicated for:

Hypertension:

• The treatment of hypertension. May be used alone or in combination with other antihypertensive agents.

Angina Pectoris:

• The long-term treatment of angina pectoris.

Myocardial Infarction:

• The treatment of hemodynamically stable patients with definite or suspected acute myocardial infarction to reduce cardiovascular mortality when used alone or in conjunction with intravenous metoprolol tartrate. Oral metoprolol tartrate therapy can be initiated after intravenous metoprolol tartrate therapy or, alternatively, oral treatment can begin within 3 to 10 days of the acute event.

Metoprolol tartrate is contraindicated in patients with: 

• sinus bradycardia
• heart block greater than first degree
• cardiogenic shock
• overt cardiac failure 
• sick-sinus syndrome
• severe peripheral arterial circulatory disorders 
• a heart rate < 45 beats/min; second-and third-degree heart block; significant first-degree heart block (P-R interval ≥ 0.24 sec); systolic blood pressure < 100 mmHg; or moderate-to-severe cardiac failure

Do not abruptly discontinue metoprolol tartrate therapy in patients with coronary artery disease. Severe exacerbation of angina, myocardial infarction and ventricular arrhythmias have been reported in patients with coronary artery disease following the abrupt discontinuation of therapy with beta-blockers. When discontinuing chronically administered metoprolol tartrate, particularly in patients with coronary artery disease, the dosage should be gradually reduced over a period of 1 to 2 weeks and the patient should be carefully monitored.  

Patients with bronchospastic disease should, in general, not receive beta blockers, including metoprolol tartrate. Because of its relative beta₁ selectivity, however, metoprolol tartrate may be used in patients with bronchospastic disease who do not respond to, or cannot tolerate, other antihypertensive treatment.

Beta blockers, like metoprolol tartrate, can cause depression of myocardial contractility and may precipitate heart failure and cardiogenic shock.

Bradycardia, including sinus pause, heart block, and cardiac arrest have occurred with the use of metoprolol. Patients with first-degree atrioventricular block sinus node dysfunction or conduction disorders may be at increased risk.

If metoprolol is used in the setting of pheochromocytoma, it should be given in combination with an alpha-blocker, and only after the alpha-blocker has been initiated. Administration of beta-blockers alone in the setting of pheochromocytoma has been associated with a paradoxical increase in blood pressure due to the attenuation of beta-mediated vasodilatation in skeletal muscle.

Catecholamine-depleting drugs (e.g., reserpine) may have an additive effect when given with beta blocking agents or monoamine oxidase (MAO) inhibitors. Observe patients treated with metoprolol plus a catecholamine depletor for evidence of hypotension or marked bradycardia, which may produce vertigo, syncope, or postural hypotension.

Both digitalis glycosides and beta-blockers slow atrioventricular conduction and decrease heart rate. Concomitant use can increase the risk of bradycardia.

Concomitant administration of a beta-adrenergic antagonist with a calcium channel blocker may produce an additive reduction in myocardial contractility because of negative chronotropic and inotropic effects.

Potent inhibitors of the CYP2D6 enzyme may increase the plasma concentration of metoprolol which would mimic the pharmacokinetics of CYP2D6 poor metabolizer. Known clinically significant potent inhibitors of CYP2D6 are antidepressants such as fluvoxamine, fluoxetine, paroxetine, sertraline, bupropion, clomipramine and desipramine; antipsychotics such as chlorpromazine, fluphenazine, haloperidol and thioridazine; antiarrhythmics such as quinidine or propafenone; antiretrovirals such as ritonavir; antihistamines such as diphenhydramine; antimalarials such as hydroxychloroquine or quinidine; antifungals such as terbinafine.

Concomitant administration of hydralazine may inhibit presystemic metabolism of metoprolol leading to increased concentrations of metoprolol.

Antihypertensive effect of alpha-adrenergic blockers such as guanethidine, betanidine, reserpine, alpha-methyldopa or clonidine may be potentiated by beta-blockers including metoprolol. Beta- adrenergic blockers may also potentiate the postural hypotensive effect of the first dose of prazosin, probably by preventing reflex tachycardia.

If a patient is treated with clonidine and metoprolol concurrently, and clonidine treatment is to be discontinued, stop metoprolol several days before clonidine is withdrawn. Rebound hypertension that can follow withdrawal of clonidine may be increased in patients receiving concurrent beta-blocker treatment.

Concomitant administration with beta-blockers may enhance the vasoconstrictive action of ergot alkaloids.

In general, administration of a beta-blocker should be withheld before dipyridamole testing, with careful monitoring of heart rate following the dipyridamole injection.

There are no adequate and well controlled studies in pregnant women. Animal studies: postimplantation loss and decrease neonatal survival.

Metoprolol is excreted in breast milk in a very small quantity.

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• Use in patients under the age of 18. GoToSource

• Use in children with marfan syndrome to slow down the progression of aortic dilation. GoToSource

• Arrhythmias. GoToSource

• Prevention of migraines. GoToSource

• Hyperthyroidism. GoToSource

• Acute stress reactions and generalized anxiety. GoToSource

Insomnia. GoToSource

Sexual dysfunction. GoToSource

Hair loss. GoToSource

Psoriatic nail disease. GoToSource

Transient left ventricular apical ballooning syndrome (heart muscle becomes suddenly weakened). GoToSource

Drug-induced carpal tunnel syndrome. GoToSource

Bradycardia (slow heart rate). GoToSource

Increased risk of heart failure hospitalizations when used in patients with ejection fraction of 50% or greater. GoToSource

Peyronie’s disease (fibrous scar tissue inside the penis) and systemic lupus erythematosus syndrome. GoToSource

No major injury lawsuits reported.