Nitroglycerin (glyceryl trinitrate) is a substance that is metabolized to nitric oxide in the cell. Its action is not dependent of the endothelium derived nitric oxide, but imitates those of this biological mediator. We thought that nitroglycerin should have the same in vivo actions as the endogenous nitric oxide in vitro has. We report and discuss the first patient with superficial thrombophlebitis successfully treated with transdermal nitroglycerin.