Comparative pharmacokinetics of three non-steroidal anti-inflammatory drugs in five bird species

Information on the pharmacokinetics and pharmacodynamics of anti-inflammatory drugs in birds is scarce. Choice of drug and of dosage is usually empirical, since studies of anti-inflammatory drugs are lacking. In this study, three common veterinary non-steroidal anti-inflammatory drugs (NSAIDs) were administered intravenously to five different bird species. Sodium salicylate, flunixin and meloxicam were selected as anti-inflammatory drugs. These NSAIDs were administered intravenously to chickens (Gallus gallus), ostriches (Struthio camelus), ducks (Anas platyrhynchos), turkeys (Meleagris gallopavo) and pigeons (Columba livia). Plasma concentrations of the drugs were determined by validated high-performance liquid chromatography methods and pharmacokinetic parameters were calculated. Most bird species exhibited rapid elimination of these drugs. Ostriches had the fastest elimination rate for all three NSAIDs, but there were some interesting species differences. Chickens had a half-life that was approximately 10-fold as long as the other bird species for flunixin. The half-life of chickens and pigeons was three-fold as long as the other bird species for meloxicam, and, for salicylic acid, the half-life in pigeons was at least three-five-fold longer than in the other bird species.