The effect of pindolol on exercise‐induced cardiac acceleration in relation to plasma levels in man

Abstract
The correlation between the beta receptor blocking activity of pindolol and plasma level was studied in 8 subjects after a 10-mg oral dose. Exercise tachycardia was markedly reduced over a period of at least 6 hr. Significant effects were recorded 30 min after the drug. For each individual there was a close correlation between log plasma level and beta blockade. The regression lines were parallel as shown by analysis of covariance; the intercepts, however, were significantly different. It can be concluded that there is a correlation between plasma level and beta adrenergic blockade by pindolol, but the data failed to establish in different individuals the blood levels necessary to achieve effective adrenergic blockade.