THE METABOLISM AND EXCRETION OF S³⁵-CHLORPROMAZINE BY THE RAT

¹ Department of Pharmacology, Purdue University, Lafayette, Indiana

The metabolic fate of S³⁵-chlorpromazine was studied in the rat. From 40 to 50% of the dose was excreted in the urine and an equivalent amount in the feces. The excretion of radioactivity was maximal during the first 36 hours and was essentially complete within 72 hours.

Four excretion products were determined qualitatively by chromatography and quantitatively as a percent of the dose: chlorpromazine (12.3%); chlorpromazine sulfoxide (5.0%); chlorpromazine sulfoxide secondary amine (5.2%); and chlorpromazine sulfoxide primary amine (2.3%). Rats excreted more of the latter metabolite and less chlorpromazine sulfoxide following pretreatment for 2 weeks with chlorpromazine.