Up to 1% of young women may have bulimia nervosa, characterised by an intense preoccupation with body weight, uncontrolled binge-eating episodes, and use of extreme measures to counteract the feared effects of overeating. People with bulimia nervosa may be of normal weight, making it difficult to diagnose. After ten years, about half of people with bulimia nervosa will have recovered fully, a third will have made a partial recovery, and 10-20% will still have symptoms.We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments for bulimia nervosa in adults? What are the effects of discontinuing treatment in people with bulimia nervosa in remission? We searched: Medline, Embase, The Cochrane Library and other important databases up to June 2007 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).We found 26 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.In this systematic review we present information relating to the effectiveness and safety of the following interventions: cognitive behavioural therapy (alone or plus exposure response prevention enhancement); cognitive orientation therapy; dialectical behavioural therapy; discontinuing fluoxetine in people with remission; guided self-help cognitive behavioural therapy; hypnobehavioural therapy; interpersonal psychotherapy; mirtazapine; monoamine oxidase inhibitors (MAOIs); motivational enhancement therapy; pharmacotherapy plus psychotherapy; pure or unguided self-help cognitive behavioural therapy (CBT); reboxetine; selective serotonin reuptake inhibitors (SSRIs); topiramate; tricyclic antidepressants (TCAs); and venlafaxine.