Bulimia nervosa is characterized by the repeated rapid consumption of large amounts of food (bingeing), followed by attempts to rid the body of the excess food consumed (purging).
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, occurring in 1.6% of females and 0.5% of males.
People repeatedly eat in binges. That is, they eat large amounts of food within a relatively short period of time, often within 2 hours. Emotional stress often triggers the binge-purge cycle, which usually is done in secret. Bingeing, 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 high-calorie 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. However, unlike in anorexia nervosa, the body weight of people with bulimia nervosa tends to fluctuate around normal.
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, people who have this disorder eat so much during a binge that their stomach ruptures or their esophagus tears, leading to life-threatening complications.
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.
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:
Technically, the diagnosis is confirmed when people describe binge-purge behavior and report having two or more binge-eating episodes a week for at least 3 months. But doctors may diagnose the disorder without this information when symptoms strongly suggest it.
The two most effective approaches to treatment are cognitive-behavioral therapy and drug therapy. Treatment may be most effective when both are used.
In cognitive-behavioral therapy, dysfunctional thoughts are identified and examined, and people are helped to give them up. People meet with a therapist 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 reduces the frequency of bingeing in about two thirds of people with bulimia and stops bingeing altogether in about one third. People who have had this therapy continue to reduce or refrain from bingeing for at least 1 year.
Selective serotonin reuptake inhibitors, a type of antidepressant, are somewhat effective and best used with cognitive-behavioral therapy in the treatment of bulimia nervosa. However, when the drugs are stopped, bingeing frequently recurs.
Last full review/revision June 2008 by Albert J. Stunkard, MD