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Bulimia Nervosa

By

Evelyn Attia

, MD, Columbia University Medical Center;


B. Timothy Walsh

, MD, College of Physicians and Surgeons, Columbia University

Last full review/revision Jul 2022| Content last modified Jul 2022
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Bulimia nervosa is characterized by recurrent episodes of binge eating followed by some form of inappropriate compensatory behavior such as purging (self-induced vomiting, laxative or diuretic abuse), fasting, or driven exercise; episodes occur, on average, at least once/week for 3 months. Diagnosis is based on history and examination. Treatment is with psychologic therapy and antidepressants.

General reference

  • 1. Udo T, Grilo CM: Prevalence and correlates of DSM-5–defined eating disorders in a nationally representative sample of U.S. adults. Biol Psychiatry 1;84(5):345-354, 2018. doi: 10.1016/j.biopsych.2018.03.014.

Pathophysiology of Bulimia Nervosa

Serious fluid and electrolyte disturbances, especially hypokalemia Hypokalemia Hypokalemia is serum potassium concentration 3.5 mEq/L ( 3.5 mmol/L) caused by a deficit in total body potassium stores or abnormal movement of potassium into cells. The most common cause is... read more , occur occasionally. Extremely rarely, the stomach ruptures or the esophagus is torn during a binge or purge episode, leading to life-threatening complications.

Because substantial weight loss does not occur, other serious physical complications that often occur with anorexia nervosa are not present. However, cardiomyopathy may result from long-term abuse of syrup of ipecac if used to induce vomiting.

Symptoms and Signs of Bulimia Nervosa

Patients with bulimia nervosa typically describe binge-purge behavior. Binges involve rapid consumption of an amount of food definitely larger than most people would eat in a similar period of time under similar circumstances (however, the amount considered excessive for a normal meal versus a holiday meal may differ) accompanied by feelings of loss of control.

Patients tend to consume sweet, high-fat foods (eg, ice cream, cake) during binge episodes. The amount of food consumed in a binge varies, sometimes involving thousands of calories. Binges tend to be episodic, are often triggered by psychosocial stress, may occur as often as several times a day, and are usually carried out in secret.

Binge eating is followed by compensatory behaviors: self-induced vomiting, use of laxatives or diuretics, excessive exercise, and/or fasting.

Patients are typically of normal weight; only a minority are have excess weight or obesity. However, patients are excessively concerned about their body weight and/or shape; they are often dissatisfied with their bodies and think that they need to lose weight.

Patients with bulimia nervosa tend to be more aware of and remorseful or guilty about their behaviors than those with anorexia nervosa and are more likely to acknowledge their concerns when questioned by a sympathetic clinician. They are also less socially isolated and more prone to impulsive behavior, drug and alcohol abuse, and overt depression. Depression Depressive Disorders Depressive disorders are characterized by sadness severe enough or persistent enough to interfere with function and often by decreased interest or pleasure in activities. Exact cause is unknown... read more , anxiety (eg, concerning weight and/or social situations) and anxiety disorders Overview of Anxiety Disorders Everyone periodically experiences fear and anxiety. Fear is an emotional, physical, and behavioral response to an immediately recognizable external threat (eg, an intruder, a car spinning on... read more are common among these patients.

Complications

Most physical symptoms and complications of bulimia nervosa result from purging. Self-induced vomiting may lead to erosion of dental enamel of the front teeth, painless parotid (salivary) gland enlargement, and an inflamed esophagus. Physical signs include

  • Swollen parotid glands

  • Scars on the back of the hand (from repeatedly inducing vomiting by using fingers to trigger gag reflex)

  • Dental erosion

Diagnosis of Bulimia Nervosa

  • Clinical criteria

  • Recurrent episodes of binge eating (the uncontrolled consumption of unusually large amounts of food) that are accompanied by feelings of loss of control over eating and that occur, on average, at least once a week for 3 months

  • Recurrent inappropriate compensatory behavior to influence body weight (on average, at least once a week for 3 months)

  • Self-evaluation that is unduly influenced by body shape and weight concerns

Diagnosis reference

  • 1. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition Text Revision, DSM-5-TRTM, Feeding and eating disorders.

Treatment of Bulimia Nervosa

  • Cognitive behavioral therapy

  • Interpersonal psychotherapy

  • Selective serotonin reuptake inhibitors (SSRIs)

Cognitive behavioral therapy is the treatment of choice for bulimia nervosa. Therapy usually involves 16 to 20 individual sessions over 4 to 5 months, although it can also be done as group therapy. Treatment aims to

  • Increase motivation for change

  • Replace dysfunctional eating with a regular and flexible pattern

  • Decrease undue concern with body shape and weight

  • Prevent relapse

cognitive behavioral therapy eliminates binge eating and purging in about 30 to 50% of patients. Many others show improvement; some drop out of treatment or do not respond. Improvement is usually well-maintained over the long-term.

In interpersonal psychotherapy, the emphasis is on helping patients identify and alter current interpersonal problems that may be maintaining the eating disorder. The treatment is both nondirective and noninterpretive and does not focus directly on eating disorder symptoms. Interpersonal psychotherapy can be considered an alternative when cognitive behavioral therapy is unavailable.

SSRIs Selective Serotonin Reuptake Inhibitors (SSRIs) Several drug classes and drugs can be used to treat depression: Selective serotonin reuptake inhibitors (SSRIs) Serotonin modulators (5-HT2 blockers) Serotonin-norepinephrine reuptake inhibitors... read more used alone reduce the frequency of binge eating and vomiting, although long-term outcomes are unknown. SSRIs are also effective in treating comorbid anxiety and depression. Fluoxetine is approved for the treatment of bulimia nervosa; a dose of 60 mg orally once a day is recommended (this dose is higher than that typically used for depression).

Key Points

Drugs Mentioned In This Article

Drug Name Select Trade
PROZAC, SARAFEM
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