High-security hospital patients are often complex in presentation characterised by treatment resistance, medication non-concordance and history of violence. Paliperidone is licensed as both an oral and depot antipsychotic for the treatment of schizophrenia. Whilst there is data for the effectiveness of paliperidone palmitate (PP), there are no studies involving patients in forensic settings or those with comorbid personality disorder.

To determine the effects of PP on violence, aggression and personality pathology.

To evaluate the clinical effectiveness of PP.

This was a retrospective service evaluation involving 11 patients. Medical records and interviews with the treating psychiatrist were used to formulate clinical global impression (CGI) and to identify incidents of violence. The effect on personality symptom domains; cognitive-perceptual, impulsive-behavioural dyscontrol and affective dysregulation was ascertained, as well as engagement with occupational and psychological therapies.

Six patients were being prescribed PP. All 6 showed improvement in the CGI score with benefits in the symptom domains. Two patients demonstrated a reduction in violence risk and 2 remained incident-free. There was improvement in engagement with therapies. Benefits were also seen in aspects of personality for those who had discontinued PP.

This pragmatic study of a small but complex patient group demonstrated that PP was effective in reducing symptoms of schizophrenia. Additionally and for the first time, it was shown that PP was also effective in reducing violence as well as improving personality pathology dimensions in a comorbid patient. This could have significant implications for management of high-security patients.