title: Pharmacokinetics of ricobendazole in calves.
abstract: The pharmacokinetics of ricobendazole (RBZ) and its major metabolite albendazole sulphone (ABZSO2) were studied in six calves, after administration of RBZ (7.5 mg/kg), using a 10% experimental solution by the intravenous (i.v.) route, a 10% commercial solution by the subcutaneous (s.c.) route, and a 10% experimental suspension by the intraruminal (i.r.) route. Blood samples were drawn during a 60-h period. Plasma drug and metabolite concentrations were determined by HPLC. The pharmacokinetic evaluation in each case was prepared by weighted least-squares nonlinear regression analysis. Ricobendazole i.v. data were best fitted by a two-compartment model. The best pharmacokinetic exponents and coefficients were estimated, and the pharmacokinetic variables for RBZ and ABZSO2 were calculated from them. Similar patterns of plasma disposition were found for RBZ after i.r. and s.c. administration, suggesting delayed release from the s.c. site resembling the slow release of the drug from the rumen.
authors.affiliation: Cátedra de Farmacología, Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral, Esperanza, Argentina.
authors.forename: E A
authors.initials: EA
authors.lastname: Formentini
authors.forename: O N
authors.initials: ON
authors.lastname: Mestorino
authors.forename: E L
authors.initials: EL
authors.lastname: Mariño
authors.forename: J O
authors.initials: JO
authors.lastname: Errecalde
mesh_terms: D015766:Albendazole / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics*; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism; D000871:Anthelmintics / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D002417:Cattle / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000662:veterinary; D018592:Cross-Over Studies; D007267:Injections / Q000662:veterinary; D007275:Injections, Intravenous / Q000662:veterinary; D007279:Injections, Subcutaneous / Q000662:veterinary; D012417:Rumen / Q000378:metabolism
chemical_list: D000871:Anthelmintics; D015766:Albendazole; C027186:albendazole sulfoxide