Bulimia nervosa(BN) is a chronic and refractory mental disorder characteristic of recurrent binge eating and weight control which mostly occur in adolescents and young women. The life-time prevalence ranges from 1.0%-4.2%, while in middle school and university, the prevalence can be 4.7-17%, and keep increasing. The recurrence rate of BN is also high, which can reach 25-63% six months after recovery. The nature cause can last several years showing a chronic feature. Patients with BN can also suffer from other severe psychosomatic complications, which harm the patients physical and mental health, thus lead to a mortality of 1% and negative impact on patients life and his/her family.

Antidepressant fluoxetine can reduce binge eating and purging behaviors in BN patients in a short time. It is the only drug approved by the US FDA for the treatment of BN, and also helps to prevent recurrence. However, there are still a considerable proportion of patients who keep a poor response to the medication. Cognitive behavioral therapy, Interpersonal therapy and other traditional psychotherapy are effective for BN patients, however, as many as 50% of BN patients still have ED symptoms. Therefore, it is necessary to develop a more effective new treatment method. Dialectical behavior therapy as a new and effective psychological therapy in the treatment of BN, proven to reduce binge eating, purging behaviors and non-suicidal act of self harm in adolescents and adults in foreign countries, now shows its superiority in the treatment of BN. At present, because of an acute shortage of psychotherapists in China, carrying out the DBT group is significant. However, currently there are no related research reports in china.

This study is to examine whether the efficacy of DBT for BN is comparable with drug treatment, whether short-term and long-term efficacy of DBT combined with drug treatment of BN is better than single DBT or single drug treatment, and trying to explore predictable biological indicators of short-term and long-term efficacy of DBT for BN. This study will use multi-center randomized controlled study design. 165 outpatients with BN will be recruited from Shanghai Mental Health Center, No.6 Hospital of Peking University and Shanghai Tongji Hospital. This study will use multi-center randomized controlled study design. 165 outpatients with BN will be recruited from Shanghai Mental Health Center, No.6 Hospital of Peking University and Shanghai Tongji Hospital. There will be three groups: DBT treatment group, Fluoxetine treatment group, DBT combined with fluoxetine treatment group. The investigator prepare to recruit 165 patients with BN ,and each group is 55, and then three groups will be given standard intervention for 12 weeks. To assess the eating disorder symptoms, impulsive and emotional change, clinical symptom scales, psychological scales and the security indexs will be used at baseline, 4 weeks, 8 weeks, 12 weeks (end of treatment), 16weeks(1 month after treatment),24 weeks (3 months after treatment) and 36 weeks (6 months after treatment follow-up). Furthermore, brain MRI will be used for DBT treatment group at baseline, and 36 weeks.

This study was designed with sufficient consideration about innovation as well as feasibility, and is to be operated on well proved theoretical basis and guidance of an operation manual. If successful, results of this study may bring great improvement to clinical practice of this refractory mental disorder.