AbstractThe pharmacokinetics of florfenicol (FFC) in green sea and hawksbill sea turtles were evaluated following intramuscular (i.m.) administration at two different dosages of 20 or 30 mg/kg body weight (b.w.). This study (longitudinal design) used 5 green sea and 5 hawksbill sea turtles for the two dosages. Blood samples were collected at assigned times up to 168 h. FFC plasma samples were analyzed using validated high‐performance liquid chromatography equipped with diode array detection. The pharmacokinetic analysis was performed using a non‐compartment approach. The FFC plasma concentrations increased with the dosage. The elimination half‐life was similar between the treatment groups (range 19–25 h), as well as the plasma protein binding (range 18.59%–20.65%). According to the surrogate PK/PD parameter (T > MIC, 2 μg/mL), the 20 and 30 mg/kg dosing rates should be effective doses for susceptible bacterial infections in green sea and hawksbill sea turtles.