A rapid high-performance thin-layer chromatographic urine screen for laxative abuse
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Updated: Nov 8, 2026

High-throughput and Comprehensive Drug Surveillance Using Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry
Published on: April 23, 2019
1Division of Biochemistry, Ottawa Civic Hospital, Ont, Canada.
Abstract:
Laxative abuse, if unrecognized, can lead to unnecessary and costly investigations. The stimulants and cathartics are the most commonly abused laxatives and have the potential for causing the most long-term damage. We have optimized a solid-phase extraction coupled with high-performance thin-layer chromatography (HPTLC) to provide rapid, simple, and 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 diarrhea of unknown origin.
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