DAO 119:67-74 (2016)  -  DOI: https://doi.org/10.3354/dao02979

ABSTRACT: We investigated the pharmacokinetic characteristics of praziquantel (PZQ) in rice field eels Monopterus albus. Pharmacokinetic parameters were determined following a single intravenous administration (5 mg kg^-1 body weight [bw]) and a single oral administration (10 mg kg^-1 bw) at 22.0 ± 0.7°C. We also evaluated residue depletion in tissues following daily administration of PZQ (10 mg kg^-1 bw) that was given orally for 3 consecutive days at 22.0 ± 0.7°C. Following intravenous treatment, the plasma concentration-time curve was best described by a 3-compartment open model, with distribution half-life (t_1/2α), elimination half-life (t_1/2β), and area under the concentration-time curve (AUC) of 0.54 h, 17.10 h, and 14505.12 h µg l^-1, respectively. After oral administration, the plasma concentration-time curve was best described by a 1-compartment open model with first-order absorption, with absorption half-life (t_1/2Ka), elimination half-life (t_1/2Ke), peak concentration (C_max), time-to-peak concentration (T_max), and AUC estimated to be 2.28 h, 6.66 h, 361.29 µg l^-1, 5.36 h, and 6065.46 h µg l^-1, respectively. The oral bioavailability (F) was 20.9%. With respect to residue depletion of PZQ, the t_1/2β values of muscle, skin, liver, and kidney were 20.2, 28.4, 14.9, and 54.1 h, respectively. Our results indicated rapid absorption, rapid elimination, and low bioavailability of PZQ in rice field eels at the tested dosing conditions.

KEY WORDS: Pharmacokinetics · Residue depletion · Praziquantel · Monopterus albus