Phenytoin intoxication induced by sulthiame in epileptic patients

Routine estimation of serum phenytoin levels in patients newly admitted to a Special Centre for Epilepsy showed that 40% of those receiving sulthiame in addition to phenytoin had levels in the toxic range. Four long-stay patients became drug intoxicated when sulthiame treatment was started. Sulthiame appears to inhibit the hepatic hydroxylation of phenytoin.