A study of the solubility of Valium in commonly used intravenous solutions showed Valium to be equally insoluble in 5% dextrose in normal saline, 5% dextrose in water, normal saline, and Ringer's lactate. However, the precipitate which was formed became completely resuspended when mixed with as little as 39-42% plasma in vitro. This would indicate that the chalky precipitate seen in the I. V. tubing when Valium is injected into a running I. V. near the venipuncture site becomes resuspended when mixed with plasma in vivo. If one elects to inject Valium into the tubing of a running I. V., it is recommended that the drug be administered slowly to assure adequate mixing with blood plasma in order to prevent the circulation of particulate matter.
Valium is currently one of the most popular drugs used in the psychosedative management of the apprehensive dental patient. Various techniques are advocated for its administration from direct injection into a vein to injection of the drug into a running I. V. However, the manufacturer states that the drug should not be added to I. V. fluids or other solutions or drugs. Presumably this is because of the formation of a cloudy precipitate immediately upon addition to aqueous solutions. Grower et al. have shown that saturated aqueous solutions of Valium in normal saline redissolve when added to plasma; however, they presented no data on the behavior of solutions of Valium added to other commonly used intravenous fluids. The present study was, therefore, undertaken to study the behavior of Valium when added to lactated Ringer's solution, 5% dextrose solutions, and normal saline; and to see how human blood plasma affects the solubility of Valium in these solutions.