Add-on effects of a low-dose aripiprazole in resolving hyperprolactinemia induced by risperidone or paliperidone

This study investigated the effects of a low-dose aripiprazole adjunctive treatment for risperidone- or paliperidone-induced hyperprolactinemia in Han Chinese women with schizophrenia. After 4 weeks of risperidone or paliperidone treatment, 60 out of 66 patients improved significantly and experienced hyperprolactinemia. They were randomly assigned to the treatment group (aripiprazole adjunctive treatment) (n=30) or control group (non-adjunctive treatment) (n=30). The dosage of risperidone and paliperidone were maintained; and aripiprazole was maintained at 5mg/day during the 8-week study period. The prolactin levels at the end of the 8th week were significantly lower in the treatment group than in the control group. The estradiol level correlated negatively with serum prolactin level both in the treatment group and the control group at the end of the 8th week and the 4th week respectively. The Positive and Negative Syndrome Scale score improved significantly during the 8-week study period in both groups. The incidence of treatment-emergent adverse event was similar in two groups. Low-dose aripiprazole adjunctive treatment is effective in relieving risperidone- and paliperidone-induced hyperprolactinemia in female schizophrenic patients without increasing adverse event.