A RAPID HIGH-PERFORMANCE THIN-LAYER CHROMATOGRAPHIC URINE SCREEN FOR LAXATIVE ABUSE

Laxative abuse, if unrecognized, can lead to unnecessary and costly in vestigations. The stimulants and cathartics are the most commonly abus ed laxatives and have the potential for causing the most long-term dam age. We have optimized a solid-phase extraction coupled with high-perf ormance thin-layer chromatography (HPTLC) to provide rapid, simple, an d sensitive detection of phenolphthalein, danthron, rhein, aloin, and bisacodyl and its metabolites in urine. Positive screens have revealed laxative abuse in 3 of 42 samples from patients presenting with diarr hea of unknown origin.