Detection of laxative abuse by urine analysis with HPLC and diode array detection

A simple method is proposed for analysis of stimulant laxatives and metabol ites of laxatives in urine. All stimulant laxatives commercially available in Germany, Begium and the Netherlands, the diphenylmethane derivatives and the anthraquinones, were included. Chromatography was performed with a sta ndardized isocratic HPLC system with diode array detection ('STIP'), which is commonly used in the Netherlands for toxicological screening. The method was validated by ingestion of a normal dose of the laxatives by human volunteers. In all cases the expected laxative metabolite could be de tected in urine twelve hours after intake. Also urine samples bf pa suspect ed of laxative abuse, were analyzed.