Arterial Flow in The Lower Leg Correlated With Plasma Levels of Two Formulations of Papaverine Hydrochloride

Abstract

In patients with severe peripheral vascular disease (mean arterial flow of 40 ml/min), a suspension of papaverine in a soft gelatin capsule produced plasma levels almost three times higher than those following treatment with a sustained- release tablet formulation. The higher plasma levels resulted in significantly greater vasodilation with increased distal arterial flow. The onset of peak pulsatile flow with the soft gelatin form came sooner than with the sustained- release form. However the durations of vasodilation were similar with both papaverine preparations. The vasodilatory activity of papaverine appeared to be greater in the sympathectomized leg. The soft gelatin formulation of papaverine may be an orally active vasodila tor, maintaining a distal runoff after reconstruction of a large artery, and may be effective in sustaining a longer vasodilatory effect in patients with small vessel disease, when surgical procedures may not be applicable.