Propanolol
Generic
Class of Drug:
Non-cardioselective b-blockers (beta-blockers).
Formulation:
Tablets, propranolol hydrochloride 10mg, 40mg, 80mg, 160mg.
Capsules, s/r, propranolol 80mg, 160mg.
Oral solution (syrup), propranolol hydrochloride 5mg/5mL, 10mg/5mL and 50mg/5mL
Clinical Indications:
Hypertension. Prophylaxis of upper gastrointestinal bleeding in patients with portal hypertension and oesophageal varices. Adjunct in thyrotoxicosis.
Dose:
Adult
Hypertension, initially, 80mg twice daily, increased at weekly intervals as required. Maintenance dose, 160-320mg daily.
Portal hypertension, initially, 40mg twice daily, increased to 80mg twice daily according to heart rate. Maximum daily dose, 160mg.
Thyrotoxicosis, 10-40mg three to four times daily.
Children
Not recommended.
Contraindications:
2nd or 3rd degree AV block, sinus bradycardia, sick sinus syndrome, severe peripheral arterial disease, uncompensated cardiac failure, cardiogenic shock, hypotension, right ventricular failure secondary to pulmonary hypertension, significant cardiomegaly, untreated phaeochromocytoma. Generally contra-indicated in patients with obstructive airways disease or a history of bronchospasm.
Cautions:
Poor cardiac reserve should be controlled with digitalis and diuretics. Diabetes. Metabolic acidosis. Asthenic symptoms. Cerebrovascular insufficiency. Atopy. Renal or hepatic impairment, thyrotoxic crisis. General anaesthesia; consider withdrawal before elective surgery. Pregnancy, lactation. Withdraw gradually.
Interactions:
Clonidine withdrawal, verapamil, diltiazem, class II calcium antagonists, class I antiarrhythmics, cardiac depressant anaesthetics, hypoglycaemics, reserpine, other antihypertensives, ergot alkaloids, cimetidine, rifampicin, theophylline, warfarin, CNS depressants, sympathomimetics, indometacin (indomethacin).
Side Effects:
Cold extremities, sleep disturbances, bradycardia, exertional tiredness, bronchospasm, heart failure, hypotension, gastrointestional upset. If unexplained dry eyes or skin rash occur withdraw gradually.