Levetiracetam, perampanel, and the issue of aggression: A self-report study

This study investigated to which degree levetiracetam (LEV) and perampanel (PER), antiseizure medications (ASM) that are both known to cause aggression and irritability, share the same or different, behavioral side-effect profiles. In this self-report study, 68 participants with epilepsy treated with LEV (n = 35) or PER (n = 33) as part of their medication were asked to rate their behavioral experience with the respective drug as positive, neutral, or negative. Results of a German adaptation of the Adverse Events Profile (AEP) and of the "FPZ", a German personality questionnaire, were analyzed as a function of drug and rating. Thirty-eight percent of the LEV group and 36% of the PER group experienced negative change after the evaluated drug was introduced. By subdividing participants in the LEV sample into those who attributed the negative effects to LEV and those with neutral or positive experience with LEV, a negative evaluation of LEV was associated with significantly worse scores in cognition, mood, and physical domains (80% versus 20-40%). Subdividing participants in the PER sample into those who attributed negative the side effects to PER, and those with a neutral or positive experience with PER, significance could be shown for mood domains only (100% versus 50%), and within this domain only for increased aggression and irritability. Comparing features of the behavioral negative side effects of LEV and PER revealed that LEV appears to have a negative impact on a much broader range of behaviors than PER, which specifically seems to induce aggression and irritability and no other psychiatric side effects. Further research should aim at different expression and different mechanisms of aggression and irritability underlying the superficially similar effects of the two drugs.