Pharmacokinetics of phenytoin in children.
1 Apparent Vmax and Km for phenytoin were estimated in 40 children (aged 8--33 months) and 21 adults (aged 18--66 years). 2 The derived values of Vmax and Km were used to predict the plasma and salivary concentrations of phenytoin following a change in dose. There was a highly significant correlation between observed and predicted steady-state concentration in both children and adults (P less than 0.001). 3 The apparent Km was similar in children (7.5 +/- 1.2 mg/l) and adults (9.4 +/- 2.3 mg/l). 4 Vmax differed significantly (P less than 0.001) between children (20.4 +/- 2.1 mg kg-1 day-1) and adults (8.7 +/- 0.7 mg kg-1 day-1). 5 After correction for differences in the ratio of liver weight to body weight in children and adults, Vmax was similar in the two groups.
D001835:Body Weight; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007700:Kinetics; D008099:Liver / Q000033:anatomy & histology; D008297:Male; D009929:Organ Size; D010672:Phenytoin / Q000378:metabolism*
D010672:Phenytoin