Abstracts

Rationale: Behavioral side effects occur in approximately 15-20% of pediatric patients taking immediate-release levetiracetam (IR-LEV). Switching to the extended-release formulation of levetiracetam (ER-LEV) may improve these symptoms. Methods: The records of pediatric patients with epilepsy who had been stable for at least 6 months on IR-LEV were retrospectively reviewed. Patients were all switched to equivalent doses of ER-LEV. The records included simple, caregiver-reported questionnaires about the patient's mood and behavior before and 3 months after the switch. The questionnaire included the terms irritability, anger, moodiness, mood swings, and depressed behavior or thinking. There also was an area for caregivers to write in concerns. Changes in seizure frequency was also evaluated. Results: Twenty-six patients ages 9-17(average 13) years old met criteria for review (11 male, 15 female). None had a change in seizure frequency. Five were on one other anti-epileptic drug (AED) and one patient was on 2 other AEDs. Sixteen patients (62%) had generalized epilepsy and 10 (38%), focal epilepsy. Twenty patients (77%) had significant improvement or resolution of their behavioral and/or mood side effects. Five (19%) had no significant change, and one patient (4%) had worsening of symptoms. Conclusions: Significant improvement of behavioral and mood side effects occur in many pediatric epilepsy patients when switched from immediate-release to extended-release levetiracetam. No change in seizure frequency was seen. A larger prospective study with more extensive mood and behavioral testing is needed.