The efficacy of long-acting injectable antipsychotics in dual schizophrenia patients has been well established.

To investigate the efficacy of long-acting injectable paliperidone palmitate(PPLAI) in the psychopathology of dual psychotic patients. To examine the tolerability profile of PPLAI in dual psychosis.

An open-label, non-interventional, prospective study was conducted in 42 dual psychotic outpatients who received PPLAI in monotherapy. We used the Brief Psychiatric Rating Scale (BPRS) to assess psychotic symptoms and the Udvalg für Kliniske Undersogelser Scale (UKU) to evaluate treatment tolerability, at baseline, and after 3 and 6 months of treatment. Prolactin levels were also determined at the time of the study inclusion and after 6 months.

Thirty-five patients were included into the study. After 6 months of treatment, patients receiving PPLAI showed a significant improvement in positive symptoms (disorganisation, suspiciousness), negative symptoms (emotional withdrawal, motor retardation, blunted affect and confusion), affective symptoms (somatic concern, anxiety and depression) and in motor symptoms (unco-operativeness, excitement). When compared to the 3rd month assessment, after 6 months, statistically significant differences were found in items 4,11,14,17 and 18. Patients receiving PPLAI had lower rates of side effects assessed by UKU Scale (asthenia, sedation, failing memory, tension, insomnia, rigidity, tremor, weight gain and sexual dysfunction). Baseline prolactin levels ranged 11–122 (mean:38), at 6 months: 20–136 (mean:38.4).

After 6 months, patients receiving PPLAI had lower psychotic symptoms, a decrease in side effects, and a significant improvement in global functioning. No changes in prolactin levels were found.