Levetiracetam (LEV) is effective for treating localisation-related epilepsy, but it is uncertain whether it is effective for treating idiopathic generalised epilepsy. We compared 12-week baseline and LEV treatment periods for patients with generalised seizure types-myoclonic, tonic-clonic and absence seizures--who had failed other anticonvulsants. The majority of 55 patients (76%) had >50% seizure reduction with LEV therapy, 40% became seizure-free; 15% discontinued LEV due to adverse events, mostly sedation. This is preliminary evidence that LEV is effective for treating idiopathic generalised epilepsy.