Microsomal enzyme induction in children: the influence of carbamazepine treatment on antipyrine kinetics, 6 beta‐hydroxycortisol excretion and plasma gamma‐glutamyltranspeptidase activity.

Abstract

1 The influence of carbamazepine (CBZ) therapy on saliva antipyrine kinetics, urinary 6 beta‐hydroxycortisol excretion and plasma gamma‐ glutamyltranspeptidase activity was determined in nine children aged 6‐ 14 years. 2 During 5 weeks of CBZ therapy the mean (+/‐ s.d.) antipyrine clearance increased from 65 +/‐ 12 ml kg‐1 h‐1 to 143 +/‐ 34 ml kg‐1 h‐1 (P less than 0.001) and the mean half‐life declined from 6.24 +/‐ 1.23 h to 2.78 +/‐ 0.59 h (P less than 0.001). The apparent volume of distribution of antipyrine did not change during CBZ treatment. 3 Urinary 6 beta‐hydroxycortisol excretion increased markedly during the study period from 5.10 +/‐ 1.77 micrograms day‐1 kg‐ 1 to 17.85 +/‐ 6.75 micrograms day‐1 kg‐1 (P less than 0.01). 4 Plasma gamma‐glutamyltranspeptidase activity increased in eight out of nine children during CBZ therapy but the change was not statistically significant. 5 CBZ appears to have a marked enzyme inducing effect in young epileptics as indicated by antipyrine kinetics and 6 beta‐ hydroxycortisol excretion. Copyright © 1982, Wiley Blackwell. All rights reserved