Efficacy and pharmacokinetics of triclabendazole in buffalo with induced fasciolosis.

A study was conducted to understand pharmacokinetics and flukicidal activity of intraruminal administration of triclabendazole (TCBZ) at 12.0, 24.0 and 36.0 mg kg-1 body weight in experimentally Fasciola gigantica-infected buffaloes on Week 2 and 10 post-infection. No fluke eggs in faeces and no flukes could be recovered from the liver of buffaloes following intraruminal administration of triclabendazole at 24.0 and 36.0 mg kg-1 body weight both on Weeks 2 and 10 post-infection, while the recommended therapeutic dose at 12.0 mg kg-1 body weight was 19-23% effective. Pharmacokinetic analysis of the data revealed a significantly higher (P < 0.05) concentration maximum of both the metabolites and area under concentration-time curve of TCBZ-SO2 in animals treated at 12.0 mg kg-1 body weight on Week 10 post-infection, whereas a significantly higher area under the concentration-curve and elimination half-life of both the metabolites and significantly higher concentration maximum and area under the concentration-time curve of both the metabolites were observed in animals treated on Week 10 post-infection at the dose rates of 24.0 and 36.0 mg kg-1 body weight, respectively. Bioavailability of triclabendazole was more in buffaloes with mature flukes than with immature flukes.