【Objective】 To analyze the effect of small doses of olanzapine on the efficacy of duloxetine and the incidence and severity of nausea and vomiting induced by duloxetine hydrochloride. 【Methods】 A total of 268 patients

who meet diagnostic criteria of major depressive disorder and somatoform disorder

from January 2009 to October 2012

were randomly divided into duloxetine hydrochloride alone group (165 cases

including 112 major depressive disorder patients

43 somatoform disorder patients) and duloxetine hydrochloride joint use of small doses of olanzapine group (103 cases

including 72 major depressive disorder patients

31 somatoform disorder patients). All patients were assessed at the first day and the end of two weeks and four weeks treatment on Hamilton Depression Scale (HAMD)

and after two weeks treatment

total scales of Treatment Emergent Symptom Scale (TESS) and the incidence and severity of nausea and vomiting were assessed. 【Results】 After two weeks and four weeks treatment

the scales of HAMD was significantly lower in duloxetine hydrochloride joint use of small doses of olanzapine group than in the duloxetine hydrochloride alone group. After two weeks treatment

the incidence of nausea and vomiting was significantly lower in duloxetine hydrochloride joint use of small doses of olanzapine group than in the duloxetine hydrochloride alone group

but no significant difference (P > 0.05) in the incidence of nausea and vomiting between different doses of olanzapine. Antiemetic effect of olanzapine work for all patients. 【Conclusion】 Small doses of olanzapine help to improve the clinical efficacy of duloxetine hydrochloride and reduce the incidence of nausea and vomiting induced by duloxetine hydrochloride

and do not increase the level of overalladverse reactions.