In the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV; APA, 1994), bulimia nervosa (BN) is classified as an eating disorder. The disease is characterized by discrete periods of binge eating during which, large amounts of food are consumed and a sense of control over eating is absent, followed by differing types of purging behaviour to prevent weight gain. Since the first descriptions of the diagnosis, little is known about the aetiological background of the disease. BN is accompanied by, or due to, alterations of serotonin and/or norepinephrine activity. These changes may possibly be involved in the pathological eating behaviour and in causing associated depression.