Nonepileptic uses of gabapentin.

For decades, antiepileptic drugs (AEDs) have been used to treat a variety of nonepileptic conditions such as chronic pain, psychiatric disorders, and movement disorders. As indicated by recent published reports, gabapentin, a relatively new AED, is useful for treating a wide range of neurologic and psychiatric conditions. Although its exact mechanism of action has yet to be determined, gabapentin is likely to have multiple effects. Unlike conventional AEDs used to treat nonepileptic disorders (e.g., carbamazepine, phenytoin, valproate) gabapentin offers the advantages of low toxicity and a favorable side-effect profile. The largest area of nonepileptic use of gabapentin is neuropathic pain, in which it has demonstrated efficacy in treatment of postherpetic neuralgia, diabetic neuropathy, and trigeminal neuralgia. It has also been reported effective as therapy for several psychiatric disorders, most notably bipolar disorder. In addition, review of the published literature reveals the usefulness of gabapentin in movement disorders, migraine prophylaxis, and cocaine dependence. Future clinical studies will provide further insight into the range of conditions for which gabapentin is effective.