A double-blind comparison of transdermal clonidine and oral captopril in essential hypertension.

In a double-blind study, patients with mild essential hypertension were randomly assigned to treatment with transdermal clonidine or oral captopril. After a two- to three-week titration period, blood pressure decreased significantly from 146.3/95.4 to 134.7/85.1 mmHg in the 33 clonidine-treated patients and from 143.0/96.1 to 134.8/87.1 mmHg in the 35 captopril-treated patients; the mean daily doses were 0.2 mg (equivalent) of clonidine and 122.9 mg of captopril. After eight weeks of treatment, blood pressures were reduced to 132.9/85.2 mmHg in the clonidine group (n = 22) and 131.2/82.5 mmHg in the captopril group (n = 16). In black patients, blood pressure reductions were greater with clonidine than with captopril. Four patients were withdrawn from treatment because of side effects in the clonidine group and one in the captopril group. No between-group differences were found in the responses to a quality-of-life questionnaire completed before and after treatment. The clonidine patches were worn during 99% of patient-weeks of treatment; captopril was taken as directed during 64% of patient-weeks of treatment. It is concluded that transdermal clonidine is safe and effective and well accepted by hypertensive patients.