The bioavailability of meperidine using urine assays for meperidine and normeperidine

The results of a two-way crossover trial of two commercial preparations of meperidine hydrochloride in 24 healthy volunteers is reported. The urinary excretion patterns resulting from dosing with the two preparations were followed for 48 hours, and the urine concentrations of meperidine and a major metabolite, normeperidine, were determined by gas liquid chromatography. Statistical analysis of the data showed no significant difference between the urine concentrations of meperidine and normeperidine produced by either preparation, and the preparations are of comparable bioavailability. The use of the urinary excretion pattern and concentrations represents a rapid, accurate, and quantitative method for determining the bioavailability of different preparations of meperidine hydrochloride.