The samples were initially screened for drugs by a Syva EMIT Toxicology System. Confirmatory testing of preliminary positive cases was accomplished using a hydrolysis, extraction, and derivatization procedure performed with a Zymark robotic system. An existing solid phase extraction method was modified extensively for this procedure. Morphine and codeine were identified using electron impact gas chromatography/mass spectrometry operating in the selective ion monitoring mode. The amount of enzyme activity needed for hydrolysis, incubation time, and incubation temperature was experimentally optimized during procedure development. It was determined that the abuse and legitimate use of codeine could usually be distinguished from heroin or morphine use by the presence of a high ratio of codeine to morphine in urine. The robotic system enabled testing for morphine and codeine to be fully automated, including the hydrolysis of urine samples. Further, the robotic system decreased human exposure to hazardous chemicals and specimens and demonstrated its reliability, accuracy, precision, and cost-effectiveness over manual techniques. 7 references, 7 tables, and 8 figures