Cardiovascular Drugs and Therapy 3: 343, 1989 © Kluwer Academic Publishers. Printed in the U.S.A.

NIFEDIPINE AND/OR ATENOLOL FOR MILD TO MODERATE HYPERTENSION: A GENERAL PRACTICE STUDY

KEY WORDS. nifedipine, atenolol, hypertension

Dear Sir

The recent nifedipine-atenolol study review commit- tee [1] reported tha t slow-release nifedipine (daily dose up to 40 mg twice per day) or atenolol (50-100 mg daily) both decreased diastolic blood pressure levels to below 95 m m H g in about two thirds of patients with mild to moderate hypertension. In the doses used, nifedipine was more effective than atenolol in reducing systolic blood pressure with equal reductions in dias- tolic blood pressure. Of the patients who did not re- spond fully to nifedipine or atenolol monotherapy, there were further modest reductions in blood pressure with the fixed-dose combination of atenolol 50 mg and nifedipine 20 mg given once daily. Thus the mean blood pressure fell by about 5-6/4 m m H g and the heart rate fell by about 5 beats/min on the combined therapy compared with the values at the end of the period of monotherapy. Regarding side effects, 12% of patients on nifedipine monotherapy were withdrawn, compared with 10% on atenolol monotherapy. Reasons for withdrawal in the case of nifedipine were flushing, headaches, dizziness, edema, and gastrointestinal upset. In the case of atenolol, withdrawals were because of headache, dizziness, or fatigue. Of the

D. Maclean 1, A.M. Heagerty ~ 1Department of Clinical Pharmacology, Ninewells Hospital, Dundee, U.K. 2Department of Medicine, Leicester Royal Infirmary, Leicester, U.K.

patients given combined therapy, 5% were withdrawn because of intolerable side effects. The addition of atenolol did not appear to reduce the side effects caused by nifedipine. Thus, in the doses used, either slow-release nifedipine or atenolol gave reasonable control of blood pressure in about two thirds of patients, and of the remainder the low-dose fixed com- bination gave slightly better control of blood pressure.

D. Maclean A.M. Heagerty

Reference

1. Nifedipine-Atenolol Study Review Committee. Nifedipine and atenolol singly and combined for treatment of essential hypertension: Comparative multicentre study in general practice in the United Kingdom. Br Med J 1988;296:468- 472.

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