The trial included 302 patients with focal and generalized forms of epilepsy, aged from 18 to 73 years (mean age 33.23±12.73 years). Oxcarbazepine (trileptal) was prescribed in accordance to recommendations and titration schemes (continuous and single-stage) conventional in Russia. Trileptal was prescribed as the start antiepileptic therapy to 46.1% of patients. In other patients, antiepileptic drugs used previously were withdrawn mainly to their low clinical efficacy and poor tolerability. The duration of the study was 12 weeks. The efficacy was assessed by the number of patients with seizures reductions of 50%. The positive therapeutic response was found in 93.2% of patients who completed the trial, and the complete reduction of seizures was achieved in 34.9%. There were also positive changes in the seizure duration, frequency of consciousness change and other post seizure phenomena. The low frequency and intensity of adverse effects during the treatment with trileptal was observed: there were 93 adverse effects in 60 patients included in the trial; 3 (3.2%) of these effects were considered as severe (dizziness in one patient, sleepiness in two patients). The adverse effects disappeared without any additional treatment.