CompositionMetoprolol (100 mg) SALT INFORMATIONMetoprolol (100 mg) TYPICAL USAGE Angina, cardiac arrhythmia, hypertension, hyperthyroidism (adjunct), maintenance of recurrent duodenal ulcers, migraine prophylaxis, myocardial infarction, prevention of relapse in duodenal ulcer. SIDE EFFECTS Agranulocytosis, hyperglycemia, severe bradycardia, bradycardia, dizziness, fatigue, nausea, vomiting, alopecia, diarrhea, dyspnea, pruritus, GI upset, elevation of liver enzymes, hyperpigmentation, sleep pattern disturbances. DRUG INTERACTION Metoprolol (Tartrate) is known to interact with other drugs like alprazolam, amiodarone (HCl), aspirin, benorylate, choline magnesium trisalicylate, cimetidine (HCl), clonidine (HCl), clorazepate (K), dexamphetamine (Sulphate), diltiazem (HCl), fluoxetine (HCl), fluvoxamine (Maleate). Always consult your physician for the change of dose regimen or an alternative drug of choice that may strictly be required. MECHANISM OF ACTION Metoprolol competes with adrenergic neurotransmitters such as catecholamines for binding at beta(1)-adrenergic receptors in the heart. Beta(1)-receptor blockade results in a decrease in heart rate, cardiac output, and blood pressure.