Venodilatory effects of nicorandil in healthy volunteers.

The effects of a single dose of nicorandil (40 mg orally) on human dorsal hand veins in vivo were assessed and compared with the effect of nitroglycerin (0.8 mg sublingually). The hand veins had been preconstricted with norepinephrine to approximately one-third of their initial size. We demonstrated that a venous relaxation occurred after administration of nicorandil and nitroglycerin. In the doses studied, the effect was more pronounced and lasted longer after nicorandil. The pharmacodynamic effects of nicorandil in humans may be explained in part by this venous relaxation.