A Pilot Study Exploring the Impact of Pro Re Nata Medication Utilization on Aggression in Forensic Psychiatric Patients.

Objective: To analyze patterns of pro re nata (PRN) medication utilization during the seven-day periods preceding and following aggressive incidents in a forensic setting, including both psychotropic and somatic agents, to identify trends in use surrounding aggression. Methods: This was a retrospective chart review at a long-term state forensic psychiatric facility. Patients housed on units associated with the New Outlook Program (NOP) within a six-month period who received PRN medications were included. Results: Out of 106 patients evaluated, 42 were included. The mean age for study participants was 37 years old, with 83% being male. Out of 322 aggressive incidents, the overall PRN utilization rate was higher than the baseline in 38.8% of events (N = 125). For the overall seven-day period preceding and following an aggressive incident, there was no significant difference between psychotropic and somatic PRNs (β = -0.16, p = 0.74), and neither type showed a meaningful deviation from baseline (Intercept = -0.25, p = 0.46). Additionally, there was no significant difference in PRN utilization when separately assessing the seven-day period preceding or following an aggressive incident. Conclusion: No consistent group-level trends in PRN utilization were identified in relation to aggression. However, some patient-level variation was observed post-incident, suggesting individualized patterns compared to group-level trends. These findings support the clinical value of monitoring individuals' PRN utilization patterns to inform treatment planning.