Topiramate in the treatment of highly refractory patients with Dravet syndrome.

The purpose of this study was to assess the effectiveness and tolerability of topiramate (TPM) as add-on therapy in children with Dravet syndrome and considered unsatisfactorily controlled using stiripentol. All the 36 patients having been treated with TPM in our centre in 2001 were retrospectively evaluated. Seventy percent of them still received stiripentol when TPM was introduced. The association of both drugs did not need any particular adaptation of dosages. The mean TPM follow-up was 13.3 months (4-25 months) and the mean optimal TPM dose was 3.2 mg/kg/d (0.6-9.2 mg/kg/d). Twenty eight children (78 %) showed more than 50 % reduction in the frequency of generalized tonic-clonic seizures and status epilepticus (SE), whereas 8 % had more than 50 % increase. Six patients (17 %) remained seizure-free for at least 4 months. The most frequently reported side-effects were gastrointestinal and behavioural disturbances. TPM had to be stopped in 17 % of patients, because of poor tolerability and/or lack of efficacy. Topiramate seems therefore to be helpful in Dravet syndrome, even in patients not satisfactorily controlled by stiripentol. Both drugs can be easily and safely associated.