Effects and safety of risperidone augmentation of fluoxetine on the treatment-resistant depression

Objective To explore the effects of low-dose risperidone augmentation of fluoxetine on the treatment-resistant depression.Methods All 101 patients with the treatment-resistant depression were randomly assigned to the two groups: a low dose (0.5—2.0 mg/d) of risperidone plus ongoing fluoxetine or fluoxetine alone. They were estimated with Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), and Treatment Emergent Symptom(TESS)at baseline and every one or two weeks subsequently. The study lasted for 4 weeks.Results (1) The 51 combining-treatment patients included 26 males and 25 females with the average age of (42±13) years. The 50 mono-treatment patients included 24 males and 26 females with the average age of (41±12) years. (2) There were significant differences on the scores of HAMD and HAMA between the two groups at the endpoint of treatment (P0.05). (3) In the augmented treatment group, 67% responded, while 26% responded in mono-therapy group. Risperidone augmentation produced greater improvement than fluoxetine mono-therapy (P0.05). (4) In risperidone-fluoxetine group, 53% of patients showed different but mild side effects, in comparison with 40% in fluoxetine group (P0.05).Conclusion Risperidone may be a useful and safe adjunct to fluoxetine in treatment of refractory depression.