Antihypertensive effect of carteolol in thiazide-treated hypertensive subjects.

The antihypertensive effect of carteolol, a new potent nonselective beta-adrenergic antagonist, was investigated in a double-blind, parallel study of 35 patients with mild-to-moderate, essential hypertension whose blood pressures were not adequately controlled with a diuretic. Patients were randomly assigned to receive placebo, carteolol 5 mg, or carteolol 20 mg once a day in addition to hydrochlorothiazide 50 mg for six weeks. Thirty-four patients completed the study: 11 patients received placebo (group 1), 12 patients received carteolol 5 mg (group 2), and 11 patients received carteolol 20 mg (group 3). After six weeks of treatment, the two groups that received carteolol had significant reductions in systolic (SBP) and diastolic (DBP) blood pressure from baseline in both the supine and standing positions. In group 2, mean SBP decreases for supine and standing positions were 11 +/- 2.1 and 11 +/- 1.9 mm Hg, respectively (P less than .01) and 8 +/- 1.2 and 9 +/- 1.3 mm Hg, respectively, for DBP (P less than .01); whereas in group 3, values were 8 +/- 2.8 and 12 +/- 3.0 mm Hg for SBP, in 5 +/- 1.9 and 9 +/- 3.1 mm Hg, respectively, for DBP (P less than .01). The hypotensive effect was associated with slight but significant decreases in heart rate (P less than .01 in group 2 and P less than .05 in group 3). Reductions in SBP and DBP with the 20-mg dose were not significantly different from those with the 5-mg dose.2+ moderate hypertension.