KEMADRIN (procyclidine hydrochloride) is a synthetic antispasmodic compound of relatively low toxicity. It has been shown to be useful for the symptomatic treatment of parkinsonism (paralysis agitans) and extrapyramidal dysfunction caused by tranquilizer therapy. Procyclidine hydrochloride was developed at The Wellcome Research Laboratories as the most promising of a series of antiparkinsonism compounds produced by chemical modification of antihistamines. Procyclidine hydrochloride is a white crystalline substance which is soluble in water and almost tasteless. It is known chemically asα-cyclohexyl-α-phenyl-1-pyrrolidinepropanol hydrochloride and has the following structural formula.