Dr. Kaye began by noting that individuals with anorexia nervosa have low serotonin levels. Serotonin is synthesized from tryptophan, an essential amino acid obtained from one's diet. Dr. Kaye suggested that people with anorexia nervosa may be self-regulating their levels of serotonin by starving themselves.

Dr. Kaye explained existing treatments for anorexia nervosa have limited efficacy and many patients have a chronic, relapsing illness or die. He said that the first generation of treatment studies focused mainly on attempts to increase the rate of weight gain of emaciated patients in a hospital setting, but the studies found that many people relapsed after discharge.
Dr. Kaye referred to more recent studies that suggest specialized treatment protocols may reduce relapse or improve outcome in some patients. Because these treatment protocols may not be available to all patients, his group proposed a new treatment strategy.

Their treatment strategy was based on the premise that anorexia nervosa is partially due to a disturbance of serotonin neuronal pathways and that malnutrition may diminish synaptic serotonin release. Because SSRIs work by blocking uptake of serotonin, they hypothesized that SSRIs may be more efficacious among patients in a well-nourished state.
Dr. Kaye reported a double-blind, placebo-controlled trial in which the SSRI fluoxetine significantly reduced relapse, obsessional behavior, and depression in women with anorexia nervosa who had achieved weight restoration.

Dr. Kaye's group also has conducted open trials of olanzapine (which often causes weight gain in patients with other psychiatric disorders) among malnourished patients with anorexia nervosa: Preliminary data suggest that olanzapine is associated with weight gain and weight maintenance as well as with reduced agitation and reduced resistance to treatment.
Dr. Kaye hypothesized that the effects of olanzapine on appetite and other behavioral symptoms may involve 5-HT₂ receptor blockade. Dr. Kaye remarked, "Successful treatment of anorexia nervosa will come from an understanding of the pathophysiology of anorexia nervosa."