Positive relationship between the dosage of pindolol and its antihypertensive effect.

Pindolol was given once a day to 15 patients with mild to moderate hypertension to investigate whether once-daily dosage controls blood pressure for 24 h and whether a paradoxical rise in blood pressure occurs with increasing dosage. Placebo and pindolol, 10, 20, and 30 mg, were administered in double-blind or single-blind fashion. Blood pressure and heart rate were determined under identical and strictly standardized conditions 24-26 h after giving the last capsule. Blood pressure levels were significantly lower during all periods of active treatment compared with placebo levels. There was a clear relation between dosage of pindolol and its antihypertensive effect. These results demonstrate the pindolol can be given once daily in the treatment of hypertension and that a paradoxical rise of blood pressure does not occur with dosages up to 30 mg pindolol daily.