Gabapentin is effective for partial and secondarily generalized seizures—that is, seizures that begin in a limited area of the brain. It does not prevent primary generalized seizures such as absence, myoclonic, or primary generalized tonic-clonic seizures, which involve both sides of the brain at the same time.

It does not interact with any other seizure medicines or other types of medication, so it is easy to use along with other seizure medicines (so-called adjunctive therapy) to treat partial epilepsy.

Gabapentin is also effective for some people when used alone (called monotherapy), although the FDA has not approved it to be used in this way.