As many of you may know, research findings indicate that at least half of all people diagnosed with an eating disorder do not meet the full criteria for either of the two primary eating disorders diagnoses (anorexia nervosa and bulimia nervosa).

According to the DSM-IV-TR, “eating disorder not otherwise specified” (EDNOS) is the diagnostic term used to describe clinically significant eating disturbances that fall outside of the complete diagnostic criteria for either anorexia nervosa or bulimia nervosa.

It is important to understand that a diagnosis of EDNOS is no less clinically significant than that of anorexia or bulimia, nor is it necessarily of less concern. EDNOS can be quite serious and requires the same attention and level of treatment as another eating disorder diagnosis.

One example of disordered eating that currently falls under the EDNOS diagnostic classification is a syndrome unofficially known as purging disorder.

According to Pamela Keel of Florida State University, purging disorder is a syndrome wherein purging (self-induced vomiting, laxative abuse, diuretic abuse, the use of enemas) follows ingestion of a small or normal amount of food, in normal weight individuals. Purging disorder differs from bulimia in research studies as well as via patient report in that binge eating episodes are virtually absent.

A recent article describes purging disorder as involving purging to influence shape or weight at least twice per week over the previous 3 months, undue influence of weight or shape in self-evaluation, absence of binge episodes, and weight within normal range.

In a May 2009 article entitled Purging Disorder in Clinical Practice and published in the Clinicians Research Digest, Keel points out that although people with purging disorder do not have classically defined binge episodes, they may experience “subjective binge episodes”, or the experience of loss of control during eating and the feeling that they have eaten too much, even if objectively few calories have been consumed.

Keel recommends that clinicians always ask their patients to describe how much and what they have eaten during reported binge episodes, inquire about the use of purging as a means of weight control, and have an accurate way of determining a patients weight (underweight, normal weight or overweight).

To date, there have been no controlled treatment research trials involving purging disorder, therefore there are no evidence-based treatments for the syndrome. While many clinicians advocate a CBT or trans-diagnostic approach to treatment of purging disorder, this topic once again highlights the need for advancing research and treatment within our field.