DOSAGE AND ADMINISTRATION Myocardial Infarction Early Treatment: During the early phase of definite or suspected acute myocardial infarction, initiate treatment with metoprolol as soon as possible after the patient’s arrival in the hospital. Such treatment should be initiated in a coronary care or similar unit immediately after the patient’s hemodynamic condition has stabilized. Begin treatment in this early phase with the intravenous administration of three bolus injections of 5 mg of metoprolol each; give the injections at approximately 2-minute intervals. During the intravenous administration of metoprolol, monitor blood pressure, heart rate, and electrocardiogram. In patients who tolerate the full intravenous dose (15 mg), initiate metoprolol tablets, 50 mg every 6 hours, 15 minutes after the last intravenous dose and continue for 48 hours. Thereafter, the maintenance dosage is 100 mg orally twice daily. Start patients who appear not to tolerate the full intravenous dose on metoprolol tablets either 25 mg or 50 mg every 6 hours (depending on the degree of intolerance) 15 minutes after the last intravenous dose or as soon as their clinical condition allows. In patients with severe intolerance, discontinue metoprolol (see WARNINGS ). Special populations Pediatric patients: No pediatric studies have been performed. The safety and efficacy of metoprolol in pediatric patients have not been established. Renal impairment: No dose adjustment of metoprolol is required in patients with renal impairment. Hepatic impairment: Metoprolol blood levels are likely to increase substantially in patients with hepatic impairment. Therefore, metoprolol should be initiated at low doses with cautious gradual dose titration according to clinical response. Geriatric patients (> 65 years): In general, use a low initial starting dose in elderly patients given their greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy. Method of administration: Parenteral administration of metoprolol should be done in a setting with intensive monitoring. Note: Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.