Treatment of mild and moderate hypertension with medroxalol, an alpha- and beta-adrenergic antagonist.

Medroxalol, a new antihypertensive agent with alpha- and beta-adrenoreceptor blocking properties in both animals and humans, was administered in a single-blind study for 12 weeks to 29 patients with mild and moderate hypertension (standing blood pressure: 188-130/130-100 mm Hg). After 4 weeks of placebo administration, treatment with oral medroxalol was begun. Six weeks later, half the subjects added hydrochlorothiazide, 12.5 mg twice daily, to medroxalol for an additional 6 weeks, and the other half added placebo. During the final 4-week period medroxalol, but not hydrochlorothiazide, was discontinued and placebo substituted. Oral medroxalol doses of 100-400 mg twice daily reduced standing diastolic pressure to less than 100 mm Hg in 21 of the 26 subjects who completed the study. Compared to the last values on placebo, mean standing blood pressure was decreased by 15.6/12.0 mm Hg during the first 6 weeks of medroxalol at mean daily doses of 388-407 mg. Addition of hydrochlorothiazide permitted some decrease in medroxalol dosage. Upon medroxalol withdrawal, blood pressure and heart rate returned toward pretreatment values, with subjects continuing on diuretic showing lower blood pressures than the untreated individuals. Tolerance to medroxalol, with or without hydrochlorothiazide, was good. Mild orthostatic dizziness was the most frequent complaint associated with therapy, but postural hypotension was not found on physical examination. Medroxalol appears to be effective and well tolerated for reducing the blood pressure of most patients with mild to moderate hypertension and may be useful for chronic oral therapy of this disease.