While hair has for sometime been analyzed for assessment of trace elements, it is only in recent years that attention has been focused on this matrix as a possible means of evaluating drug impregnation. This technique was applied to treated subjects and drug abusers for determination of drug consumation. The method involved decontamination in ethanol, solubilization in sodium hydroxide at 100 degrees C for 10 min, extraction in chloroform/isopropanol/n-heptane (50:17:33, v/v), separation on a BP-5 capillary column (GC) and detection by mass spectrometry. Hair samples were analysed for barbiturates, antidepressants, benzodiazepines, beta-blockers, nicotine, opiates, benzoylecgonine, cannabis and amphetamines.