Lopresor

What is it?

A cardioselective 13-bloeker available as film-coated, scored tablets in 2 strengths; pink tablets contain 50mg of metoprolol tartrate and light blue tablets contain 100mg, all marked GEIGY. Also, LOPRESOR SR, available as scored, yellow, sustained-release capsule-shaped tablet marked CG/CG and CDC/CDC on the reverse, containing 200mg of metoprolol tartrate.

Medical Uses

Prevention of mortality after myocardial infarction (MI), supraventricular arrhythmias (Lopressor only), angina, high blood pressure, additional treatment in thyrotoxieosis, prevention of migraine.

Dosage

Adults, Lopressor, see literature for initial dosage after MI, 200mg each day for maintenance with treatment continuing for at least 3 months. Arrhythmias, 50mg twice or 3 times each day to a daily maximum of 300mg. Angina, Lopressor, 50-100mg 2 or 3 times each day; Lopressor SR, 1 tablet each day, increasing to 2, once per day if necessary. High blood pressure, Lopressor, 100mg daily to begin with, increasing if necessary to 200mg in 1 or more divided doses; Lopressor SR, 1 tablet each day taken in the morning. Thyrotoxicosis, Lopressor, 50mg, 4 times each day or 1 tablet of Lopresor SR in the morning. Migraine, Lopressor, 100-200mg each day in divided doses or lx Lopressor SR taken in the morning.

Special Care

Pregnancy, breast-feeding, liver or kidney disease, diabetes, metabolic acidosis, poor cerebral blood supply, history of bronchospasmn, those undergoing anaesthesia; patients with weak hearts should be treated with digitalis and diuretics. Drug should be stopped gradually.

Avoid Use

Children, patients with asthma, heart diseases including heart block, heart shock, slow heartbeat rate, heart failure.

Possible Drug and Food Interactions

Cardiac depressants, anaesthetics, reserpine, sedatives, class II calcium antagonists, anti- hypertensives, sympathomnimetics, cimetidine, indomethacin, ergot- amine, class I antiarrhythmic drugs, verapamil, clonidine withdrawal, hypoglycaemics, rifampicin, warfarin, ibuprofen.

Known Side Effects

Sleep disturbance, cold feet and hands, slow heartbeat, fatigue on exercise, wheeziness, heart failure, gastro-intestinal disorders; dry eyes or skin rash (stop use gradually), hair loss, low blood pressure, thrombocytopenia (abnormal decline in blood platelets).