PURPOSE: The role of levetiracetam in different epileptic, nonepileptic, neurologic, and psychiatric disorders is discussed. SUMMARY: Levetiracetam, an antiepileptic drug (AED), was first approved as an adjunctive therapy for the treatment of partial epilepsy in adults. It is currently being used in the treatment of multiple seizure disorders, including generalized tonic-clonic; absence; myoclonic, especially juvenile myoclonic; Lennox-Gastaut syndrome; and refractory epilepsy in children and adults. Data are emerging on possible uses of levetiracetam outside the realm of epilepsy because of its unique mechanisms of action. There is preliminary evidence about the efficacy of levetiracetam in the treatment of different psychiatric disorders, including anxiety, panic, stress, mood and bipolar, autism, and Tourette's syndrome. The most serious adverse effects associated with levetiracetam use are behavioral in nature and might be more common in patients with a history of psychiatric and neurobehavioral problems. CONCLUSION: Levetiracetam is an effective AED with potential benefits in other neurologic and psychiatric disorders. The benefit-risk ratio in an individual patient with a specific condition should be used to determine its optimal use. Levetiracetam's use in nonepileptic conditions is not recommended until more data become available from larger trials.