Purging disorder, an eating disorder marked by purging of food without binge eating, is looking for some respect. It is currently classified under the Eating Disorder Not Otherwise Specified diagnosis, meaning that it does not meet the criteria for the formally defined disorders (anorexia nervosa and bulimia nervosa). But there is evidence that purging disorder is more than a milder form of bulimia.
Note that research on purging disorder is sparse, and that future research will refine what appears to be true today.
Definition of Purging Disorder
Purging disorder has a concise, two-part definition. A person with purging disorder:
- purges food but does not binge eat; purging occurs after normal or even small amounts of food.
- maintains normal or near-normal weight.
If there is binge eating at least twice a week in addition to these criteria, the person qualifies instead for a diagnosis of bulimia nervosa. If the person purges but does not maintain a normal or near-normal weight, the diagnosis would likely be anorexia nervosa, purging type.
Purging Disorder Symptoms
Physical Symptoms
The physical symptoms of purging disorder will include all those of bulimia nervosa associated with purging, including:
- Tooth decay: Stomach acid will erode tooth enamel when a person vomits repeatedly to rid herself of food.
- Scarred hands: The back of the hand becomes scarred by contact with the teeth when inducing vomiting.
- Dehydration: Much of what is purged from the body by vomiting or laxative use is vital fluids.
- Amenorrhea: The menstrual cycle needs fuel to function properly.
- Esophageal tears: Pressure on the esophagus from vomiting can rupture it in certain cases.
- Electrolyte imbalance: Purging food forces potassium, sodium, and chloride from the body. An electrolyte imbalance can be extremely dangerous.
- Cardiac arrhythmias: These can occur because of electrolyte imbalances.
- Chronic bowel problems: Constant laxative use may train the body to need laxatives even for normal digestion.
Mental Symptoms
Those with purging disorder seem to have a greater chance of having a mood disorder (for example, depression or bipolar disorder) or anxiety disorder in addition to the eating disturbance.
Behavioral Symptoms
Obviously, the hallmark behavior of purging disorder is some form of purging of food. Most purging occurs by vomiting; some use laxatives, diuretics, or excessive exercise.
Also, those with purging disorder may be more likely than others to behave impulsively. Behaviors associated with bulimia that might be present in those with purging disorder include sexual promiscuity, cutting (or other self-harm), and shoplifting.
Differences Between Purging Disorder and Bulimia
In some ways, symptoms of purging disorder are less severe than the same symptoms in bulimia nervosa. People struggling with bulimia generally purge more often and will have more concern about eating in general. Also, those with bulimia may be more likely than those with purging disorder to have anxiety or mood disorders (though both anxiety and mood disorders are more common in purging disorder than in the general population).
Evidence that the disorders are different includes the stability of each disorder. Over a six-month study period, it was rare to see people with purging disorder develop bulimia or vice versa. Also, research suggests that serotonin and other brain chemicals in those who binge may have lesser effects than the same chemicals in those who don't. Because those with purging disorder do not binge, this would suggest that brain chemistry in the two populations is different.
Sources:
Anorexia Nervosa and Related Eating Disorders, Inc. "Less-well-known eating disorders and related problems." Accessed 8 June 2007.
Henig, Robin Marantz. "Sorry. Your eating disorder doesn't meet our criteria." New York Times, 30 November 2004.
Keel, Pamela K., Alissa Haedt, and Crystal Edler. "Purging disorder: An ominous variant of bulimia nervosa?" International Journal of Eating Disorders 38(3), Nov 2005. pp. 191-199.
