Pharmacokinetics and residues of a new oral amoxicillin formulation in piglets: a preliminary study.
The pharmacokinetics of amoxicillin (Amx) were determined in pigs following intravenous (IV) administration of a single dose of 15 mg/kg and a single dose of 15 mg/kg of a new oral formulation (Amx-FP containing 10% amoxicillin). Residue studies were performed to determine residues in edible tissues of healthy pigs after chronic oral administration of Amx-FP at a daily dose of 15 mg/kg for five consecutive days. After IV administration, the plasma concentration was characteristic of a two-compartment open model. The main pharmacokinetic variables were: t(1/2lambda(n)), MRT=90.1 min, V(darea)=0.81 L/kg and Cl(b)=3.9 mL/kg/min. After single oral administration the main pharmacokinetic variables were: C(max)=758 mug/L, t(max)=347 min and Cl(b/f)=3.7 mL/kg/min for Amx-FP. The oral bioavailability (F) was calculated at 11% for Amx-FP. Based on maximum residue levels (MRL) for AMX in pigs established at 50 microg/kg for all tissues, the withdrawal times of AMX in muscle and skin plus fat were estimated (95% tolerance limit and 95% confidence) to fall below the MRL after a withdrawal period of seven days. Levels of AMX in the liver and kidneys were estimated to fall below the MRL after a withdrawal period of four days.
Hernandez
Esther
E
Department of Pharmacology and Physiology, Faculty of Veterinary Science, University of Zaragoza, Miguel Servet 177, Zaragoza 50013, Spain.
Rey
Raquel
R
Puig
Mariona
M
Garcia
Maria Angeles
MA
Solans
Carlos
C
Bregante
Miguel Angel
MA
D000658:Amoxicillin / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D004334:Drug Administration Schedule; D004350:Drug Residues; D006207:Half-Life; D007275:Injections, Intravenous; D013552:Swine; D014018:Tissue Distribution
D000900:Anti-Bacterial Agents; D000658:Amoxicillin