The effects of long-acting pinacidil on intra-arterial blood pressure.

We have tested the efficacy of a new long-acting preparation of pinacidil, an arterial vasodilator, using continuous intra-arterial ambulatory blood pressure recording. An acute dose produced a measurable effect lasting for 12 h. The duration of this effect was less during chronic twice daily drug administration. Side effects were common, causing two out of nine patients to withdraw from the study. Tilt testing produced no postural hypotension and there was no evidence of rebound hypertension on the withdrawal day.