Pharmacokinetics of indomethacin in poultry

Indomethacin (INDO) is a nonsteroidal antiinflammatory drug widely used sin ce the 1970s. The pharmacokinetic behavior of INDO (2 mg/kg) has been studi ed after intravenous (IV) and oral administration to broiler chickens. Afte r IV administration, a first fast distribution phase and a later and slower elimination phase were observed. The elimination half-lift and mean reside nce time (MRT) obtained were 1.0 hr and 0.8 hr, respectively. After oral ad ministration, a flip-flop phenomenon was observed giving an elimination hal f-life and MRT approximately three times and six times higher, respectively , than the IV administration. The plasma concentrations after oral administ ration were sustained during 8-10 hr, giving an antinflammatory cover over the dose producing 50% of maximal effect during this time period.