SIGMA RECEPTOR-BINDING AGENT

PROBLEM TO BE SOLVED: To prepare a sigma receptor-binding pharmaceutincal agent highly effective in antagonism or pungency to a sigma receptor, having safety and useful as a preventive, therapeutical and ameliorative agent, etc., for schizophrenia and aporioneurosis by including a specific benzylpiperidine derivative as an active component. SOLUTION: This pharmaceutical agent is prepared by including a benzylpiperidine of formula I [the bond of formula II is a single or double bond; R is an atomic group of formula III or the like; R is H or a lower alkoxy; (n) is 0-4] or its pharmacologically acceptable salt [e.g. 1-benzyl-4-(3,4- dihydro-4-oxoquinazolin-3-yl)piperidine, or the like] as an active component. The dose of the compound of formula I is pref. 1-500 mg/day and the pharmaceutical agent is oral administration, by intravenous injection, by intramuscular injection, by per rectum administration or by percutaneous administration.