Bulimia nervosa is an eating disorder 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).
- People eat large amounts of food, then make themselves vomit, use laxatives, diet, fast, or vigorously exercise to compensate.
- Doctors suspect the diagnosis when people are overly concerned about their weight and their weight fluctuates a lot.
- Cognitive-behavioral therapy, a selective serotonin reuptake inhibitor (a type of antidepressant), or both may be used to treat the disorder.
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 who are deeply concerned about body shape and weight.
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 the amount considered excessive 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 physical discomfort.
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.
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In an attempt to counteract the effects of the excess food, people use various means to compensate:
- Purging—for example, by making themselves vomit (self-induced vomiting) or taking laxatives or diuretics (drugs that cause the kidneys to excrete more water)
- Rigorously dieting or fasting
- Any combination of the above
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.
Unlike in binge eating disorder, people with bulimia nervosa try to compensate for excessive eating by purging or other means.
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 with bulimia nervosa are 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.
- A doctor's evaluation
Doctors diagnose bulimia nervosa when people, particularly young women, do the following:
- Report binge eating at least once a week for 3 months or more
- Feel out of control during and after the binge
- Compensate for the binges by purging (for example, by making themselves vomit or using laxatives), by fasting, or by exercising excessively
- Express marked concern about weight gain and base their self-image largely on weight and body shape
Doctors also check for other clues that support the diagnosis of bulimia nervosa:
- Wide fluctuations in weight, especially if there are clues suggesting excessive laxative use (such as diarrhea and abdominal cramps)
- Swollen salivary glands in the cheeks
- Scars on the knuckles from using the fingers to induce vomiting
- Erosion of tooth enamel from stomach acid
- A low level of potassium detected by a blood test
- Psychologic therapy
- Certain antidepressants
Treatment of bulimia nervosa may include cognitive-behavioral therapy, interpersonal psychotherapy, and drug therapy.
Cognitive-behavioral therapy is usually used. Goals are
- To motivate people to change
- To establish and maintain a regular and flexible pattern of eating
- To reduce their preoccupation with body weight and shape
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.
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