Abstract
A systematic approach for evaluating the abuse of drugs in patients presenting to the hospital emergency room is presented from the laboratory point of view. This comprehensive screen involves qualitative colorimetric tests, ultraviolet (UV) spectrophotometry, thin layer chromatography (TLC), gas chromatography (GC), and gas chromatography - mass spectrometry (GC-MS). Laboratories with varying resources can adopt the screen presented. Thirty-two cases were evaluated with the methodology; these included tricyclic antidepressants, benzodiazepines, phencyclidine, methaqualone, and barbiturates. Increasing misuse of drugs requires that the clinical laboratory have a systematic approach to identify and confirm the presence of these drugs in emergency room patients.