Rectal administration of sodium valproate in children.

A study of VPA based on a comparison of mean plasma levels, plasma peak latency times and plasma half-lives after rectal and oral administration was conducted in 9 children between 6 months and 10 years of age suffering from various forms of epileptic seizure, before they received chronic VPA treatment. Each child received an oral dose of 20 mg/kg and after two days a rectal dose of 20 mg/kg and the mean plasma concentrations were determined at intervals for both modes of administration. An identical plasma concentration for both after 24 h showed that the quantity of drug absorbed was the same. The mean half-life varied according to age: 11 +/- 2 h for children over 3 years of age and 9 +/- 1 h for those under 3. The results of the study, in line with the few other available published data, thus confirm the validity of rectal VPA administration.