Comparative study of the multiple dose pharmacokinetics and the tolerance of a new NSAID (droxicam) versus piroxicam in healthy volunteers.

A controlled, randomized, double-blind, clinical trial has been performed in healthy volunteers in order to study the pharmacokinetics and tolerability of droxicam in comparison with piroxicam, when both drugs were administered at a dose of 20 mg/day for 20 days. Since transformation into piroxicam takes place in the gastrointestinal tract, unchanged droxicam was not detected in plasma. Steady state of plasma piroxicam concentrations was reached in all volunteers during the course of the study. Absorption kinetics of droxicam were delayed with respect to those of piroxicam (t1/2 a = 7.55 h for droxicam and 1.78 h for piroxicam). The remaining pharmacokinetical parameters studied showed no statistically significant differences. The bioavailability of both drugs was equal. Tolerability of droxicam and piroxicam was as usual for the NSAIDs, and no clinical or analytical side effects which could hinder its administration to wider populations were detected. Statistically significant differences in the number and type of side effects detected in the two treatment groups were not encountered.