Effects of age on the pharmacokinetics of single dose sulfamethazine after intravenous administration in cattle.
Sulphonamides are still being used widely, influenced by the low cost and the efficacy against many common bacterial infections, since they present a broad spectrum of activity. The aim of this study was to determine the effect of age on the pharmacokinetic/pharmacodynamics (PK/PD) integration of intravenous sulfamethazine (60 mg/kgbw) in cattle, and the possible therapeutic outcomes. Six healthy female calves, at the age of one, three, seven and fifteen weeks were used. Normality analysis was assessed with the Shapiro-Wilk test. Non-parametric tests for paired data were used. Plasma concentrations were quantified using HPLC/uv. Differences were found between one-three-weeks-old calves and seven-fifteen-weeks-old calves, in pharmacokinetic parameters (clearance, area under the concentration-time curve and elimination half-life) and in the PK/PD integration. The ratios obtained in PK/PD integration (T>MIC, WAUC) confirm that it is necessary to apply twice the dose of sulfamethazine in > or = 7 weeks-old cattle to reach a satisfactory dosage regimen (MIC > or = 32 microg/mL).
Baroni
Eduardo E
EE
Departamento de Farmacología, Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral, Esperanza, Santa Fe, Argentina.
Díaz
Diego C
DC
Picco
Eduardo
E
Waxman
Samanta
S
Rodríguez
Casilda
C
San Andrés
Manuel I
MI
Boggio
Juan C
JC
D000375:Aging / Q000502:physiology*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D002417:Cattle; D004305:Dose-Response Relationship, Drug; D005260:Female; D006207:Half-Life; D007275:Injections, Intravenous; D008826:Microbial Sensitivity Tests; D013418:Sulfamethazine / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*
D000900:Anti-Bacterial Agents; D013418:Sulfamethazine