Pediatric experience with gabapentin (GBP), a new antiepileptic drug (AED), is limited. We described 3 learning disabled children, 1 aged 7 and 2 aged 10 years, with intractable partial seizures who developed severe behavioral problems while receiving modest doses of GBP. The children became hyperactive and had explosive outburst consisting of aggressive and oppositional behavior. The behavioral problems were sufficiently severe to require discontinuation of GBP despite moderately improved seizure control.