PLASMA PHARMACOKINETICS OF INTRAVENOUS AND INTRAMUSCULAR FUROSEMIDE IN THE CAMEL (CAMELUS-DROMEDARIUS)

Single bolus intravenous (i.v.) and intramuscular (i.m.) doses of furo semide (1.5 mg kg(-1)) were administered in a crossover design to thre e female and three male adult, dromedary camels. Plasma furosemide con centrations were assayed by HPLC and sodium, potassium and chloride co ncentrations were measured using ion-selective electrodes. Plasma furo semide concentration-time plots indicated multi-compartment dispositio n, and there was considerable intersubject variability in the pharmaco kinetic parameters. The mean (so) i.v. terminal elimination half-life was 118 (67) minutes. The systemic clearance was 5.4 (1.2) mi min(-1) kg(-1), and the steady-state volume of distribution was 0.43 (0.14) li tre kg(-1). The mean absorption time after i.m. dosing was 33 (62) min utes, while the absolute bioavailability was 71 (20) per cent. The glu curonide metabolite of furosemide was not detected in plasma. Clearanc e was lower, volume of distribution was larger, and half-life was long er compared with published data for dogs, horses, rats and humans. Pla sma potassium and sodium concentrations were significantly diminished (P<0.05) by an average of 35.6 per cent (two to six hours post-dose) a nd 11.3 per cent (eight hours post-dose), respectively. Plasma chlorid e concentrations were not significantly affected by furosemide adminis tration.