Neurochemistry and Pharmacological Treatments: Where is the Field of Anorexia Nervosa Heading?

Anorexia nervosa is a debilitating psychiatric disorder characterized by severe dietary restriction and lifethreatening weight loss. The onset of the disorder typically occurs during adolescence with 90-95% of all cases occurring in females. Often characterized by a chronic and relapsing course, anorexia nervosa has one of the highest mortality rates of any psychiatric disorder. Although the etiology is unknown, a complex interplay of genetic, neurobiological, and environmental variables appear to factor into the development of the disorder. Accumulating evidence supports altered serotonin 5-HT1A, 5-HT2A, and 5-HTT receptor binding in anorexia nervosa, with more recent studies examining dopamine D2/D3 receptor binding. Despite this increasing knowledge of neurotransmitter alterations, there are few effective treatment strategies, with pharmacological treatments having minimal efficacy during the acute phase of illness. Thus, the goal of this paper is to provide an overview of neurochemical alterations during the ill state and following long-term recovery. This will be followed by a review of pharmacological treatment studies of anorexia nervosa that will focus on the limited efficacy of SSRIs and more promising findings from atypical antipsychotics. Given the combination of receptors targeted by newer generation atypical antipsychotics, these drugs may provide a more efficient means for modulating the neurobiological disturbances seen in anorexia nervosa.