Pharmacokinetics and pharmacodynamics of piroxicam in dogs.

Piroxicam was administered to beagle dogs intravenously and orally at a dose rate of 0.3 mg/kg bodyweight. It had an elimination half-life of 40.2 hours, a volume of distribution of 0.29 +/- 0.02 litres/kg and a body clearance rate of 0.066 litres/hour. When administered orally it was 100 per cent bioavailable and maximum plasma concentrations were achieved quickly (3.1 +/- 1.0 hours). Piroxicam inhibited the generation of thromboxane B2 in the blood of dogs by more than 70 per cent and more than 50 per cent inhibition was maintained in most animals for 48 hours.