Sudden withdrawal of propranolol in patients with angina pectoris.

On 51 of 53 occasions, sudden withdrawal of propranolol from patients with angina pectoris produced no substantial adverse effects. Two patients experienced a recurrence of unstable angina with one man sustaining a fatal myocardial infarction ten days after propranolol withdrawal. These observations suggest that patients with previous unstable angina may be dependent upon beta-adrenoceptor blockade. Sudden cessation of propranolol for short periods may be preferable to tapering the dosage if prolonged periods of sub-optimal beta-adrenoceptor blockade are to be avoided.