Abstracts

When seeking the best combination of antiepileptic drugs (AED), information regarding the most efficacious combination is often lacking. Most clinicians rely on their experience with seizure control and toxicity when deciding which combination to select. This may result in ill-advised biases against some combinations. To assess Oxcarbazepine tolerability as adjunctive therapy in children, we focused on the incidence of hyponatremia before and after reduction of the concomitant AED. In this study we prospectively assessed 6 children less than 4 years of age (mean age of 17 months years) with inadequately-controlled partial seizures. Oxcarbazepine was added to other AED (3 with Valproate, 1 with Phenobarbital, 1 with Levetiracetam, 1 with Carbamazepine, 1 with Gabapentin). When hyponatremia (sodium less than 130 mEq/L) occurred, reduction of the concomitant AED was authorized. Hyponatremia occurred in 2 children and was associated with lethargy. Both children were receiving high doses (40 mg/kg/day) of Oxcarbazepine concomitantly with Valproate. Reduction or discontinuation of the Valproate resulted in a rapid correction of the hyponatremia. Oxcarbazepine-induced hyponatremia improves when Valproate dosage is reduced. Further studies are needed to demonstrate if competition of Valproate with Oxcarbazepine for the hepatic glucuronidation is responsible for the increased Oxcarbazepine toxicity.