title: Pharmacokinetics and oral bioavailability of sulfadiazine and trimethoprim in broiler chickens.
abstract: Sulfonamides and trimethoprim are chemotherapeutics that are extensively used in various animal species. Little information about the pharmacokinetics of these compounds in chickens exists in the literature. In this study, a new commercial formulation of sulfadiazine in combination with trimethoprim was administered both intravenously and orally, according to a crossover design, to healthy, 7-week-old broilers. The plasma concentrations of the drugs were determined by validated high-performance liquid chromatographic methods, and pharmacokinetic parameters were calculated. After intravenous or oral administration of trimethoprim (6.67 mg/kg body weight) and sulfadiazine (33.34 mg/kg body weight), both active substances were rapidly eliminated from the plasma. There was a mean half-life of 1.61 h for trimethoprim and 3.2 h for sulfadiazine. The apparent volumes of distribution (2.2 and 0.43 L/kg, respectively, indicated that the tissue distribution of trimethoprim was more extensive than that of sulfadiazine. The oral bioavailability was approximately 80% for both components.
authors.affiliation: Department of Pharmacology, Pharmacy and Toxicology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium. kris.baert@rug.ac.be
authors.forename: K
authors.initials: K
authors.lastname: Baert
authors.forename: S
authors.initials: S
authors.lastname: De Baere
authors.forename: S
authors.initials: S
authors.lastname: Croubels
authors.forename: P
authors.initials: P
authors.lastname: De Backer
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001682:Biological Availability; D002645:Chickens / Q000097:blood*; D018592:Cross-Over Studies; D004338:Drug Combinations; D006207:Half-Life; D013411:Sulfadiazine / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D014295:Trimethoprim / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D000096926:Benzenesulfonamides
chemical_list: D000890:Anti-Infective Agents; D004338:Drug Combinations; D013411:Sulfadiazine; D014295:Trimethoprim; C024873:sulfadiazine, trimethoprim drug combination; D000096926:Benzenesulfonamides