A randomized double-blind trial of gabapentin monotherapy in patients with newly diagnosed partial epilepsy was conducted by an international study group. Gabapentin in 74 patients in each of 3 dosage groups (300, 900, or 1800 mg/day) was compared to open-label carbamazepine in 74 patients (600 mg/day) in a 24-week trial. Time to exit the study because of seizure recurrence (3 partial, 1 generalized tonic-clonic, or status) or adverse events was longer for patients taking gabapentin in doses of 900 or 1800 mg/day than 300 mg/day. Withdrawal rate was similar for carbamazepine and 1800 mg/day gabapentin (54% versus 57%) but lower for gabapentin 900 mg/day (44%). After day 30, the 900 mg/day group had the highest number of patients remaining in the study. Adverse events were more frequent in carbamazepine-treated patients (84%) than in those receiving gabapentin (60%). Rash occurred with 12% of carbamazepine and only 1% of gabapentin-treated patients. [1]

COMMENT. Gabapentin in doses of 900 or 1800 mg/day is an effective and relatively safe monotherapy for newly diagnosed partial epilepsy. The low incidence of skin rash and the lack of interaction with other antiepileptic drugs offer advantages over carbamazepine.