Withdrawal of long-term therapy with atenolol in hypertensive patients.

1 The offset of effects on blood pressure and heart rate after cessation of long-term therapy (19 +/- 3.6 months) with atenolol (200 mg once/daily) was studied in six hypertensive patients. 2 Withdrawal of atenolol resulted in a gradual return of lying, standing and post-exercise systolic and diastolic blood pressure levels and heart rate towards the baseline value. The offset of effect greatly exceeded the time for elimination of atenolol. 3 No significant differences in the pharmacokinetic profile of atenolol were evident between the values obtained following chronic dosing and an acute single-dose study. 4 The lack of clinical evidence of increased cardiac adrenergic sensitivity or rebound hypertension following withdrawal of atenolol contrasts with reports of a withdrawal syndrome following cessation of therapy with propranolol. Nevertheless until the mechanism of the propranolol-withdrawal syndrome is better understood caution is required when stopped therapy with atenolol in patients with severe coronary artery disease.