Bulimia nervosa is characterized by the repeated rapid consumption of large amounts of food (binge eating), followed by attempts to compensate for the excess food consumed (for example, by purging, fasting, or exercising).
As in anorexia nervosa, bulimia nervosa is influenced by hereditary and social factors. Also as in anorexia nervosa, most people who have bulimia nervosa are young women, are deeply concerned about body shape and weight, and belong to the middle or upper socioeconomic classes. Bulimia nervosa affects mainly adolescents and young adults. In a given year, about 1 in 100 young females have bulimia nervosa. The disorder is much less common among males.
People with bulimia nervosa have repeated episodes of binge eating. That is, they eat much larger amounts of food than most people would eat in a similar time under similar circumstances. The amount considered excessive for a normal meal may differ from that for a holiday meal.
Emotional stress often triggers the binges, which are usually done in secret. Binge eating, which is accompanied by a feeling of a loss of control, usually includes eating when not hungry and eating to the point of pain.
People tend to consume sweet, high-fat foods, such as ice cream and cake. The amount of food consumed varies and sometimes involves thousands of calories. Binges may occur as often as several times a day.
In an attempt to counteract the effects of the excess food, people use various means to purge:
Many also take diuretics to treat perceived bloating.
Unlike in anorexia nervosa, the body weight of people with bulimia nervosa tends to fluctuate around normal. Only a few are overweight or obese.
Self-induced vomiting can erode tooth enamel, enlarge the salivary glands in the cheeks (parotid glands), and inflame the esophagus. Vomiting and purging can lower potassium levels in the blood, causing abnormal heart rhythms. Sudden death can result from an abnormal heart rhythm in people who repeatedly take large quantities of ipecac to induce vomiting. Rarely, during a binge or purge, the stomach ruptures or the esophagus tears, leading to life-threatening complications.
People may be preoccupied with and judge themselves based on their weight and body shape. Their self-esteem is largely based on their body weight and shape.
Compared with people who have anorexia nervosa, those who have bulimia nervosa tend to be more aware of their behavior and to feel remorseful or guilty about it. They are more likely to admit their concerns to a doctor or other confidant. Generally, people with bulimia nervosa are more outgoing. They also are more prone to impulsive behavior, drug or alcohol abuse, and depression. They are anxious about their weight and about participation in social activities.
Bulimia nervosa is suspected when people, particularly young women, express marked concern about weight gain and have wide fluctuations in weight, especially if there is evidence of excessive laxative use (such as diarrhea and abdominal cramps).
Doctors also check for other clues:
Doctors diagnose bulimia nervosa when people report binge eating followed by purging once a week for at least 3 months and base their self-image largely on their weight and shape.
Treatment may include cognitive-behavioral therapy, interpersonal psychotherapy, and drug therapy.
Cognitive-behavioral therapy is usually used. Goals are
People meet with a therapist—individually or in a group—once or twice a week over a period of 4 to 5 months, for a total of about 16 to 20 sessions. Cognitive-behavioral therapy eliminates binge eating and purging in about 30 to 50% of people with bulimia. Many others also improve, but others drop out of therapy or do not respond. Those who improve usually continue to do well.
Interpersonal psychotherapy is an alternative when cognitive-behavioral therapy is unavailable. It helps people identify and change interpersonal problems that may be contributing to the eating disorder. This therapy does not involve telling people how to change, does not interpret their behavior, and does not deal directly with eating disorder.
Selective serotonin reuptake inhibitors, a type of antidepressant, can reduce the frequency of binge eating and vomiting, but how effective these drugs are in the long term is not clear. These drugs also effectively treat anxiety and depression, which are common among people with bulimia nervosa.
Last full review/revision December 2014 by Evelyn Attia, MD; B. Timothy Walsh, MD