The influence of pindolol and hydrochlorothiazide on blood pressure, and plasma renin and plasma lipid levels.

After three weeks' administration of placebo, three groups of eight patients with moderate hypertension were randomly assigned to single daily dose, double-blind treatment with either pindolol 15 mg, hydrochlorothiazide 50 mg, or a combination of both for eight weeks. All determinations were made 24 hours after ingestion of a dose. Reductions in supine, sitting, and standing systolic and diastolic blood pressure were greater in patients receiving hydrochlorothiazide than in those administered pindolol; however, the greatest reductions were registered in individuals receiving combination therapy. Mean basal plasma renin activity rose significantly from 0.45 +/- 0.44 to 1.42 +/- 1.31 ng/mL/hr and from 0.67 +/- 0.46 to 1.27 +/- 0.83 ng/mL/hr in patients receiving hydrochlorothiazide and combination therapy, respectively, but there was no change in those administered pindolol. Hydrochlorothiazide and combination therapy increased mean total cholesterol levels from 247 +/- 25 to 263 +/- 37 mg/dL and 198 +/- 36 to 211 +/- 33 mg/dL, respectively, at eight weeks, and both increased mean triglyceride concentrations at two weeks. Pindolol did not show any tendency to alter lipid levels. Pindolol should be given twice daily. At 15 mg daily, it has little or no effect on basal plasma renin activity or plasma lipid levels.