Felbamate as add-on therapy.

Felbamate is a novel anti-epileptic drug (AED) which has recently been associated with reports of aplastic anaemia and liver failure. We have conducted an open-label add-on assessment of the tolerability and efficacy of this compound in 111 adult patients with refractory epilepsy attending a tertiary referral centre. The mean follow-up period was 4 months (range 1-8 months). Sixty-three (57%) were ongoing, 38 (34%) had discontinued felbamate and a further 10 (9%) were withdrawing. Reasons for discontinuing felbamate were adverse events in 23 (21%), increase in seizures in 11 (10%) and lack of efficacy in 14 (12%). Behavioural disturbances occurred in 14 patients, being the most likely adverse event to result in discontinuation. No cases of aplastic anaemia or liver failure were observed in this group. Felbamate appears to be a broad-spectrum AED. Seven percent of the patients had more than 95% seizure reduction (2 patients were seizure free), whilst a further 13% had significant improvement ( > 50% reduction in seizure frequency). In conclusion, felbamate seems to be an effective AED. In view of its association with potentially life-threatening complications, its use should however be restricted to patients with medically refractory epilepsy.