Drug screening: evaluation of the Toxi-Lab TLC system.

An evaluation of a commercial TLC Kit System (Toxi-Lab) is described. The performance of the system is assessed in the detection of drugs in overdose and in therapy, and is compared with a GC drug screening system. Toxi-Lab performed well in investigating drug overdoses. We found data on metabolite patterns essential for the identification of drugs in urine and for this reason the system performed much better than GC screening in which information on metabolites is limited. In our experience Toxi-Lab screening was not sufficiently sensitive for the detection of commonly prescribed psychiatric drugs taken in therapeutic doses. This system is rapid, versatile and suitable for small laboratories, but is comparatively expensive and some expertise is necessary to interpret results. A major deficiency of the kit is that the identification procedures are designed for the detection of drugs available in the USA and many drugs prescribed in the UK have been omitted.