Toxicological and pathological findings are described in fatalities involving pentazocine (Talwin) and tripelennamine (Pyribenzamine). Procedures using thin-layer chromatography, gas chromatography, ultraviolet spectrophotometry, and spectrophotofluorometry are described, as well as the quantitative analysis of biological specimens of drug abuse and homicide victims. Microscopic findings in lung specimens from drug abuse deaths are also described.