IN HYPERTENSION METOPROLOL TARTRATE IS USUALLY GIVEN IN AN INITIAL DOSE OF 100 MG DAILY BY MOUTH, INCREASED WEEKLY ACCORDING TO RESPONSE TO 400 MG DAILY; IT MAY BE TAKEN AS A SINGLE DAILY DOSE OR TWICE DAILY. A USUAL MAINTENANCE DOSE IS 100 TO 200 MG DAILY. SOME MANUFACTURERS RECOMMEND THAT THE DOSE SHOULD BE TAKEN WITH OR IMMEDIATELY FOLLOWING A MEAL.
THE USUAL DOSE FOR ANGINA PECTORIS IS 50 TO 100 MG TWO OR THREE TIMES DAILY BY MOUTH.
IN THE TREATMENT OF CARDIAC ARRHYTHMIAS THE USUAL DOSE IS 50 MG TWO OR THREE TIMES DAILY BY MOUTH, INCREASED IF NECESSARY UP TO 300 MG DAILY IN DIVIDED DOSES.
FOR THE EMERGENCY TREATMENT OF CARDIAC ARRHYTHMIAS METOPROLOL TARTRATE MAY BE GIVEN INTRAVENOUSLY IN AN INITIAL DOSE OF UP TO 5 MG ADMINISTERED AT A RATE OF 1 TO 2 MG/MINUTE; THIS MAY BE REPEATED, IF NECESSARY, AT INTERVALS OF 5 MINUTES TO A TOTAL DOSE OF 10 TO 15 MG. WHEN ACUTE ARRHYTHMIAS HAVE BEEN CONTROLLED, MAINTENANCE THERAPY MAY BE STARTED WITH DOSES NOT EXCEEDING 50 MG THREE TIMES DAILY BY MOUTH 4 TO 6 HOURS AFTER INTRAVENOUS THERAPY.
ARRHYTHMIAS MAY BE PREVENTED ON INDUCTION OF ANAESTHESIA OR CONTROLLED DURING ANAESTHESIA, BY THE SLOW INTRAVENOUS INJECTION OF 2 TO 4 MG; FURTHER INJECTIONS OF 2 MG MAY BE REPEATED AS NECESSARY TO A MAXIMUM TOTAL DOSE OF 10 MG.
METOPROLOL IS ALSO USED AS AN ADJUNCT IN THE EARLY MANAGEMENT OF ACUTE MYOCARDIAL INFARCTION. TREATMENT SHOULD BE GIVEN WITHIN 12 HOURS OF THE ONSET OF CHEST PAIN; METOPROLOL TARTRATE 5 MG SHOULD BE GIVEN INTRAVENOUSLY AT 2-MINUTE INTERVALS TO A TOTAL OF 15 MG, WHERE TOLERATED. AFTER 15 MINUTES, IN PATIENTS WHO HAVE RECEIVED THE FULL INTRAVENOUS DOSE, ORAL TREATMENT SHOULD BE STARTED; 50 MG IS GIVEN EVERY 6 HOURS FOR 2 DAYS. IN PATIENTS WHO HAVE FAILED TO TOLERATE THE FULL INTRAVENOUS DOSE A REDUCED ORAL DOSE SHOULD BE GIVEN AS, AND WHEN, THEIR CONDITION PERMITS. SUBSEQUENT MAINTENANCE DOSAGE IS 100 MG GIVEN TWICE DAILY BY MOUTH. IN PATIENTS WHO DID NOT RECEIVE METOPROLOL BY INTRAVENOUS INJECTION AS PART OF THE EARLY MANAGEMENT OF MYOCARDIAL INFARCTION, METOPROLOL 100 MG TWICE DAILY BY MOUTH MAY BE STARTED ONCE THE CLINICAL CONDITION OF THE PATIENT STABILISES.
IN THE MANAGEMENT OF STABLE, SYMPTOMATIC HEART FAILURE METOPROLOL SUCCINATE MAY BE GIVEN AS A MODIFIED-RELEASE PREPARATION. THE INITIAL DOSE IS THE EQUIVALENT OF METOPROLOL TARTRATE 12.5 TO 25 MG ONCE DAILY, INCREASED AS TOLERATED, AT INTERVALS OF 2 WEEKS, TO A MAXIMUM OF 200 MG ONCE DAILY.
AS AN ADJUNCT IN THE TREATMENT OF HYPERTHYROIDISM METOPROLOL TARTRATE MAY BE GIVEN IN DOSES OF 50 MG FOUR TIMES DAILY BY MOUTH. DOSES OF 100 TO 200 MG ARE GIVEN DAILY IN DIVIDED DOSES FOR MIGRAINE PROPHYLAXIS.