Pharmacokinetics of levamisole in the red-eared slider turtles (Trachemys scripta elegans).

Abstract

The pharmacokinetics and bioavailability of levamisole were determined in red-eared slider turtles after single intravenous (IV), intramuscular (IM), and subcutaneous (SC) administration. Nine turtles received levamisole (10mg/kg) by each route in a three-way crossover design with a washout period of 30days. Blood samples were collected at time 0 (pretreatment), and at 0.25, 0.5, 1, 1.5, 3, 6, 9, 12, 18, 24, 36, and 48hr after drug administration. Plasma levamisole concentrations were determined by a high-performance liquid chromatography assay. Data were analyzed by noncompartmental methods. The mean elimination half-life was 5.00, 7.88, and 9.43hr for IV, IM, and SC routes, respectively. The total clearance and volume of distribution at steady state for the IV route were 0.14Lhr-1 kg-1 and 0.81L/kg, respectively. For the IM and SC routes, the peak plasma concentration was 9.63 and 10.51μg/ml, respectively, with 0.5hr of Tmax . The bioavailability was 93.03 and 115.25% for the IM and SC routes, respectively. The IM and SC route of levamisole, which showed the high bioavailability and long t1/2ʎz , can be recommended as an effective way for treating nematodes in turtles.