Penbutolol in the Treatment of Mild to Moderate Essential Hypertension in Black South Africans

Abstract

The antihypertensive effects of penbutolol, a nonselective beta‐adrenoceptor antagonist with intrinsic sympathomimetic activity, was assessed in nonobese black South Africans aged 25 to 65 years with uncomplicated mild to moderate essential hypertension. After a 4‐week placebo run‐in period 50 patients entered a randomized placebo‐controlled study with a crossover design. For 8 weeks they received a once daily dose of 40 mg penbutolol (or placebo) which was increased to 80 mg per day for the next 4 weeks in poor responders. This was followed by a 4‐week placebo washout period after which a crossover of treatment was achieved and a second 12‐week period of treatment initiated. Thirty‐five patients completed the whole study and in 15 patients diastolic blood pressure was reduced below 95 mm Hg. The mean systolic pressures of these patients decreased by 21 mm Hg and their mean diastolic pressure decreased by 11 mm Hg during treatment with penbutolol. These results suggest that penbutolol monotherapy is an alternative therapeutic approach to hypertension in black South Africans.