Exploring Clozapine's Efficacy in Managing Aggression: A Multiple Single-Case Study in Forensic Psychiatry

Background: Aggression remains a significant challenge in forensic psychiatry, yet its treatment is insufficiently researched due to practical and ethical constraints. While atypical antipsychotics are commonly used to treat aggression, clozapine has demonstrated enhanced efficacy in managing aggression across various psychiatric disorders. However, studies focusing on clozapine's effectiveness in forensic populations are limited. Objectives: This research employs a retrospective multiple single-case design to investigate the impact of clozapine on aggression, testing the hypothesis that clozapine would reduce both impulsive and psychotic aggression. Materials and Methods: Seven patients with severe aggression were studied. Clozapine treatment commenced at 12.5 mg, gradually increasing to 300 mg over two to four weeks, with individualized adjustments based on blood levels, therapeutic effects, and side effects. The first prescription date marked the start of treatment. Measurements were conducted at least two weeks prior to initiating clozapine treatment and continued for a minimum of eight weeks thereafter, extending up to 16 weeks or until patient transfer. Aggression levels were assessed using the Brøset Violence Checklist [BVC] risk assessment instrument. BVC scores were pooled and averaged weekly. Results: Results indicated a positive response to clozapine in four out of five patients with psychotic aggression, while those with impulsive aggression did not show similar improvements. Conclusion: The findings from this study suggest that clozapine may be a promising treatment option for managing aggression in forensic psychiatric populations, particularly for those exhibiting severe impulsive and psychotic aggression.