Gastrointestinal Nematode-Induced Modulation of Albendazole Biotransformation in Goats

The influence of subclinical nematodosis on kinetic disposition of albendazole (ABZ) was evaluated in goats following intraruminal administration of the drug. Plasma levels of albendazole sulphoxide (ABZ-SO) was significantly (P<0.05) higher in goats with zero epg (eggs per g) of faeces. Pharmacokinetic analysis of data revealed significantly (P<0.05) higher concentration maximum (C_max), time to reach C_max(T_max) and area under the concentration-time curve (AUC) in goats with zero epg of faeces, while significantly (P<0.05) lower bioavailability of ABZ-SO could be observed in goats with <2000 and >2000 epg of faeces. Extrapolation of data of the active metabolite ABZ-SO levels in terms of drug-parasite contact with different levels of parasitism revealed that the parasites are exposed to the lethal toxic levels for a lesser duration following intraruminal administration of the drug in goats with subclinical nematodosis.