title: Pharmacokinetics, urinary excretion and dosage regimen of levofloxacin following a single intramuscular administration in cross bred calves.
abstract: The pharmacokinetics and urinary excretion following single intramuscular administration of levofloxacin at a dose of 4 mg/kg was investigated in seven male cross bred calves. Appreciable plasma concentration of levofloxacin (0.38+/-0.06 microgram/ml) was detected at 1 min after injection and the peak plasma level of 3.07+/-0.08 microgram/ml was observed at 1 h. The drug level above MIC90 in plasma was detected up to 12 h after administration. Rapid absorption of the drug was also evident by the high value of the absorption rate constant (2.14+/-0.24 /h). The overall systemic bioavailability of levofloxacin, after intramuscular administration, was 56.6+/-12.4%. The high value of AUC (7.66+/-0.72 mg.h/ml) reflected the vast area of body covered by drug concentration. Extensive distribution of the drug into various body fluids and tissues was noted by the high value of Vd(area) (1.02+/-0.05 l/kg). The high ratio of AUC/MIC (76.6+/-7.25) obtained in this study indicated excellent clinical and bacteriological efficacy of levofloxacin in calves. The elimination half-life and MRT were 3.67+/-0.4 h and 5.57+/-0.51 h, respectively. The total body clearance (Cl(B)) was 204.9+/-22.6 ml/kg/h. On the basis of the pharmacokinetic parameters, a suitable intramuscular dosage regimen for levofloxacin in calves would be 1.5 mg/kg repeated at 12 h intervals.
authors.affiliation: Department of Pharmacology and Toxicology, College of Veterinary Science, Guru Angad Dev Veterinary and Animal Science University, Ludhiana-141004, India. vkdumka@yahoo.com
authors.forename: Vinod K
authors.initials: VK
authors.lastname: Dumka
authors.forename: Anil K
authors.initials: AK
authors.lastname: Srivastava
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D019540:Area Under Curve; D001682:Biological Availability; D002417:Cattle / Q000378:metabolism* / Q000652:urine; D006207:Half-Life; D007273:Injections, Intramuscular / Q000662:veterinary; D064704:Levofloxacin; D008297:Male; D015242:Ofloxacin / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine
chemical_list: D000900:Anti-Bacterial Agents; D064704:Levofloxacin; D015242:Ofloxacin