Efficacy of topiramate for intractable childhood generalized epilepsy with epileptic spasms: with special reference to electroencephalographic changes.

Purpose: Epileptic spasms (ES) beyond infancy are a highly refractory type of seizures that require the development of an effective treatment. We therefore studied the efficacy and safety of topiramate (TPM), which is a drug that is indicated to be effective for intractable childhood epilepsy, for ES.

Methods: Out of 58 children with ES, we enrolled 33 patients treated with TPM at ≤ 12 years of age. The administration of TPM was limited to cases of epilepsies that were resistant to any other potent treatment. We retrospectively investigated the efficacy of TPM for seizures and changes in electroencephalogram (EEG) findings.

Results: The median age at the start of TPM treatment was 5 years, 8 months. All patients had ES and 28 also had tonic seizures. As for the efficacy of TPM for all seizures, five patients became seizure-free and two had a ≥ 50% reduction in seizures. Seizure aggravation was observed in six patients. Of 29 patients whose EEG findings were compared before and during TPM treatment, nine showed EEG improvement with reduced epileptic discharges. Adverse effects were observed in 13 patients and included somnolence, anorexia, and irritability. In general, TPM was well tolerated.

Conclusions: TPM can be effective at suppressing very intractable ES in a proportion of patients who do not respond to any other treatment. The efficacy of TPM may be predictable based on EEG changes observed early in the course of treatment. TPM is promising for the treatment of extremely intractable childhood epilepsy and it has largely tolerable adverse effects.