Vetrabutine is a spasmolytic agent. As a musculotropic spasmolytic agent vatrabutine was reported to act directly on the smooth muscle fibers and to have no neurotropic activity. In pigs, its activity was specific to the uterine body and cervical musculature where it acted on the myometrial cells, sealing off the membrane against the passage of potassium ions, thereby increasing membrane potential and lowering tonus. Vetrabutine was of moderate acute oral toxicity. Vetributine hydrochloride has been used in human medicine as a spasmolytic agent in obstetrics.