ABSTRACT
Levetiracetam is a new antiepileptic drug that is used widely in Korea. It has reported behavioral side effects, most notably irritability, agitation, and aggressive behavior. However, these behavioral side effects are often not considered by prescribers and psychiatrists. We report a 64-year-old male with a cerebral astrocytoma who was referred to the department of psychiatry for increased aggression and irritability. The severity of symptoms did not fluctuate over a 24-hour period, and there was no evidence of depression (Clinical Global Impression of depression severity score: 2). The scores of scales for delirium and cognitive function did not support the possible diagnosis of delirium or dementia [Korean Mini-Mental State Examination (K-MMSE): 25; Korean version of the Delirium Rating Scale-Revised-98: 5]. The severity of aggression was very high in the trait questions of the Korean adaptation of the State-Trait Anger Expression Inventory (STAXI-K: 34). After ruling out dementia, delirium, depression, and an organic mental disorder, we thought that the aggression and irritability might be related to levetiracetam, and recommended discontinuing it without treating the symptoms. After discontinuing the levetiracetam, the patient and caregiver reported a dramatic improvement in the aggression and irritability within 3 days, and the score on the STAXI-K decreased to 10. Twenty-eight weeks follow up after consultation, the STAXI-K was 10, and K-MMSE was increased to 26. We considered a final diagnosis of other substance (levetiracetam)-related disorder not otherwise specified because of the temporal relationship between the use of levetiracetam, occurrence of the symptoms, and improvement on withdrawing the drug. The behavioral side effects of levetiracetam should be considered, especially in patients who develop behavioral changes while taking the drug.