PHARMACOLOGY: Hyoscine Butylbromide exerts a spasmolytic action on the smooth muscle of the gastrointestinal, biliary and genitourinary tracts. As a quarternary ammonium derivative, Hyoscine Butylbromide does not enter the central nervous system. Therefore, anticholinergic side effects at the central nervous system do not occur. Peripheral anticholinergic action results from a ganglion blocking action within the visceral wall as well as from an antimuscarinic activity.