Paliperidone extended-release (ER) is an atypical antipsychotic that presents the active metabolite of risperidone (9-hydroxyrisperidone) using OROS® technology [1]. Multinational placebo-controlled studies have shown paliperidone ER 3- 15 mg/day to be both efficacious and safe, with discontinuation rates due to adverse events (AEs) similar to placebo [2].

Seventy-eight female patients who were diagnosed as schizophrenia according to DSM-IV-TR and who were started on the treatments of risperidone or paliperidone included to present study. The serum prolactine levels were measured before and after 5 weeks of treatment.

The 35 of patients were treated with paliperidone, while 43 patients were given oral risperidone treatment. The increases in serum prolactine levels were significant in both groups (p≤0.001), however the increase was much more in paliperidone group. Furthermore, discontinuation rates due to indirect effects of prolactine increase such as galactorrhea, amenorrhea were higher in paliperidone group compared with risperidone group.

Beside the efficacy and well tolerability of paliperidone extended-release, the increase of prolactine level and associated side effects should be carefully assessed during treatment specifically in young women patients.