[Identification of a metabolite of floctafenine in urinary calculi]

There are three 4-amino-quinolines used for their analgesic properties: glafenine, antrafenine and floctafenin. Urinary calculi due to glafenine have been described since 1980. Recently two cases of renal calculi containing antrafenic acid have been reported. We discovered a metabolite of floctafenin in a bladder calculus and describe its identification by infrared spectrophotometry and thin-layer chromatography.