The compatibility, stability, and availability of morphine sulfate and meperidine hydrochloride prepared in total parenteral nutrient (TPN) solution, 5% dextrose injection, and sterile water for injection in polyvinyl chloride (PVC) bags were evaluated. A 300-mg dose of each narcotic was mixed in 0.25-L bags of 5% dextrose injection and sterile water for injection, and in 3-L bags of TPN and sterile water for injection. Each solution was examined visually for precipitation, color change, turbidity, and the evolution of gas immediately after the addition of the drug to the bag and every 12 hours for a 36-hour period. Narcotic concentrations in each solution were determined by high-pressure liquid chromatography before and for 36 hours after the addition of the drugs to the bags. No loss of either drug because of adsorption to the PVC bags was found. Morphine sulfate and meperidine hydrochloride were chemically compatible and stable in TPN and 5% dextrose injection for 36 hours. Solutions of morphine sulfate or meperidine hydrochloride in PVC bags containing TPN or 5% dextrose injection are visually and chemically compatible, as well as stable and available for 36 hours when stored at 21.5 degrees C with no protection from environmental light.