Identification of misused drugs in the clinical laboratory. I. Tricyclics.

A systematic approach evaluating the abuse of tricyclic drugs in the hospital emergency room from the laboratory point of view is presented. 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 facilities and resources can adapt the present screen. Amitriptyline, doxepin, loxapine and desipramine misuse were identified and confirmed using the proposed methodology in 14 cases. Increasing misuse of tricyclic antidepressants requires that the clinical laboratory have a systematic approach to identify and confirm the presence of these drugs in emergency room patients.