[Pharmacokinetics of cefprozil in infant and adult beagle dogs]

The Pharmacokinetics of cefprozil was studied upon oral administration of 25 mg/kg to fasted infant and adult Beagle dogs. When the pharmacokinetic parameters between infant and adult dogs were compared, the mean peak concentration (Cmax) in infant dogs (21.2 micrograms/ml) was significantly (P < 0.01) lower than that of adult dogs (27.8 micrograms/ml). But significant differences were not found in the areas under the concentration-time curve (AUC, in infant dogs: 121 micrograms.hr/ml, in adult dogs: 130 micrograms.hr/ml), half-lives (T 1/2, in infant dogs: 4.7 hours, in adult dogs: 4.7 hours) or urinary recovery rates (UR, in infant dogs: 36.3%, in adult dogs: 34.7%) between the 2 groups. These results suggest the distribution volumes of infant dogs are larger than those of adult dogs, and the absorption rates of infant dogs are slower than those of adult dogs, whereas the absorption quantities are similar.