Pharmacokinetics of meloxicam in red-eared slider turtles (Trachemys scripta elegans) after single intravenous and intramuscular injections

Abstract

OBJECTIVE To determine the pharmacokinetics of meloxicam after single IV and IM injections in red-eared slider turtles (Trachemys scripta elegans). ANIMALS 8 healthy red-eared slider turtles. PROCEDURES Turtles received 1 dose of meloxicam (0.2 mg/kg) IV or IM (4 turtles/route), a 30-day washout period was provided, and then turtles received the same dose by the opposite route. Blood samples were collected at predetermined times for measurement of plasma meloxicam concentration. Pharmacokinetic values for each administration route were determined with a 2-compartment open model approach. RESULTS For IV administration, mean ± SD values of major pharmacokinetic variables were 1.02 ± 0.41 hours for distribution half-life, 9.78 ± 2.23 hours for elimination half-life, 215 ± 32 mL/kg for volume of distribution at steady state, 11.27 ± 1.44 μg•h/mL for area under the plasma concentration versus time curve, and 18.00 ± 2.32 mL/h/kg for total body clearance. For IM administration, mean values were 0.35 ± 0.06 hours for absorption half-life, 0.72 ± 0.06 μg/mL for peak plasma concentration, 1.5 ± 0.0 hours for time to peak concentration, 3.73 ± 2.41 hours for distribution half-life, 13.53 ± 1.95 hours for elimination half-life, 11.33 ± 0.92 μg•h/mL for area under the plasma concentration versus time curve, and 101 ± 6% for bioavailability. No adverse reactions were detected. CONCLUSIONS AND CLINICAL RELEVANCE Long half-life, high bioavailability, and lack of immediate adverse reactions of meloxicam administered IM at 0.2 mg/kg suggested the possibility of safe and effective clinical use in turtles. Additional studies are needed to establish appropriate administration frequency and clinical efficacy.