Residency · Residency · Child Adolescent Psychiatry

Binge Eating Disorder and Bulimia Nervosa in Adolescents

Overview

Binge eating disorder (BED) and bulimia nervosa (BN) are under-recognized eating disorders in adolescents, often overshadowed clinically by anorexia nervosa. BN has a prevalence of approximately 1-2% in adolescents, while BED prevalence is approximately 1-3%. Both disorders are associated with significant psychiatric comorbidity — depression, anxiety, impulsivity, and substance use — as well as medical morbidity. CBT-Enhanced (CBT-E), adapted for adolescents, is the primary evidence-based psychotherapy. BN is more common in females, though males are increasingly recognized, while BED has a more even gender distribution. Lisdexamfetamine is FDA-approved for moderate-to-severe BED in adults, and evidence in adolescents is emerging.

Bulimia Nervosa in Adolescents

Diagnostic Criteria (DSM-5)

BN requires recurrent episodes of binge eating, defined as eating an unusually large amount of food in a discrete time period with a sense of loss of control. It also requires recurrent inappropriate compensatory behaviors to prevent weight gain, including self-induced vomiting, laxative or diuretic misuse, fasting, and excessive exercise. Both binge eating and compensatory behaviors must occur at least once per week for 3 months. Self-evaluation is unduly influenced by body shape and weight. The diagnosis cannot be made exclusively during episodes of AN.

Clinical Presentation in Adolescents

Adolescents with BN are often normal weight or overweight, which can significantly delay diagnosis. Binge eating is typically secretive, occurring after school when the adolescent is home alone or late at night. Evidence of purging may include frequent bathroom trips after meals, running water to mask vomiting sounds, calluses on the knuckles (Russell sign), dental erosion, and parotid gland enlargement. There is a preoccupation with body shape and weight, with frequent body checking or avoidance. Mood instability, impulsivity, and shame around eating behaviors are common. The adolescent may present with comorbid depression, self-harm, or substance use before BN itself is identified. Adolescents frequently minimize symptoms due to shame, making direct, non-judgmental questioning essential.

Medical Complications

Dental erosion (perimolysis — erosion of enamel on the lingual surface of teeth from repeated vomiting) is a characteristic finding. Parotid gland enlargement produces "chipmunk cheeks" from repeated vomiting. Esophageal tears (Mallory-Weiss tears) are rare but dangerous, presenting with hematemesis. Electrolyte imbalances are the most medically dangerous complication, with hypokalemia carrying cardiac arrhythmia risk, metabolic alkalosis resulting from vomiting, and metabolic acidosis resulting from laxative abuse. Dehydration and renal complications may develop. Menstrual irregularities are common. Ipecac toxicity, if the patient is using ipecac to induce vomiting, can cause cardiomyopathy. Chronic laxative abuse leads to cathartic colon, electrolyte depletion, and dependence.

Binge Eating Disorder in Adolescents

Diagnostic Criteria (DSM-5)

BED requires recurrent episodes of binge eating with the same definition as in BN. Binge episodes must be associated with three or more of the following: eating much more rapidly than normal, eating until uncomfortably full, eating large amounts without physical hunger, eating alone due to embarrassment, and feeling disgusted, depressed, or guilty afterward. Marked distress about binge eating must be present. Episodes occur at least once per week for 3 months. Critically, there is no regular use of compensatory behaviors, which is what distinguishes BED from BN.

Clinical Presentation in Adolescents

BED often presents with overweight or obesity, though not all patients with BED are overweight. Eating in secret, hiding food, and missing food from the kitchen are common patterns. Binges are frequently triggered by negative emotions — stress, sadness, boredom, or loneliness — constituting emotional eating. The sense of loss of control is the defining feature, more so than the absolute amount eaten. Significant shame and distress about eating behavior are present. BED is associated with weight-related bullying and weight stigma. It may not be recognized as an eating disorder by families or providers who focus on weight rather than the disordered behavior.

Relationship to Obesity

BED is present in approximately 25-30% of adolescents seeking weight management. It is distinct from non-eating-disordered obesity because loss of control and distress are the distinguishing features. Weight-focused interventions that do not address the underlying BED can actually worsen binge eating. Bariatric surgery candidates should be screened for BED.

Assessment

Clinical Interview

Binge eating should be screened for in all adolescents presenting with concerns about weight, eating, mood, or impulsivity. Non-judgmental, normalizing language is effective: "Many teens find themselves eating more than they intended. Has this happened to you?" The assessment should cover binge frequency, size, triggers, loss of control, compensatory behaviors, and body image concerns. A detailed eating pattern analysis should distinguish meals from snacking from binges, recognizing that skipping meals often precedes binges. Comorbid depression, anxiety, ADHD, substance use, and self-harm should be screened for. A history of dietary restriction, which frequently precedes and perpetuates binge eating, should be assessed.

Rating Scales

The EDE-Q (Eating Disorder Examination Questionnaire) is a self-report measure of eating disorder symptoms with an adolescent version available. The Binge Eating Scale (BES) provides severity measurement for BED. The SCOFF questionnaire is a brief five-question screening tool suitable for primary care settings.

Treatment

CBT-Enhanced (CBT-E) for Adolescents

Fairburn's transdiagnostic CBT-E is the most evidence-based psychotherapy for both BN and BED. Adapted for adolescents, it includes parental involvement. Key components include establishing a regular eating pattern of 3 meals plus 2-3 snacks to eliminate long gaps between eating that trigger binges. Self-monitoring through a food diary captures binges, purges, triggers, and associated emotions. Cognitive restructuring challenges body image distortions, all-or-nothing thinking about food, and perfectionism. Addressing dietary restraint targets the rigid food rules and restriction that perpetuate binge-purge cycles. Body image work addresses body checking and avoidance behaviors and helps develop body acceptance. Relapse prevention identifies and prepares strategies for managing triggers.

Family-Based Treatment for BN (FBT-BN)

FBT adapted from the AN model has evidence supporting its efficacy for adolescent BN (Le Grange et al., 2007). Parents supervise meals to prevent binge-purge episodes and work to establish regular eating patterns within the family. The phase structure parallels FBT for AN: parental control, gradual return of autonomy, and adolescent identity development.

Interpersonal Psychotherapy for Adolescents (IPT-A)

IPT-A addresses the interpersonal difficulties that trigger and maintain binge eating. Focus areas include interpersonal deficits, role transitions, grief, and interpersonal disputes. There is evidence for BED in adults and some evidence for adolescents.

Dialectical Behavior Therapy (DBT)

DBT targets emotional dysregulation as a driver of binge eating, teaching skills in mindfulness, distress tolerance, emotion regulation, and interpersonal effectiveness. It is particularly useful when binge eating serves an affect regulation function and may be combined with other approaches.

Pharmacotherapy

Pharmacotherapy Comparison

For Bulimia Nervosa

Fluoxetine is the only FDA-approved medication for BN (approved for adults and used off-label in adolescents). The recommended dose is 60 mg/day, which is higher than the typical antidepressant dose. It reduces binge-purge frequency and is most effective when combined with CBT. Other SSRIs (sertraline, fluvoxamine) have less evidence but may be used.

For Binge Eating Disorder

Lisdexamfetamine (Vyvanse) is FDA-approved for moderate-to-severe BED in adults and reduces binge eating frequency through a stimulant mechanism. Its use in adolescents is off-label with emerging evidence, and clinicians must weigh the benefits against stimulant risks including abuse potential, cardiovascular effects, and appetite suppression. SSRIs reduce binge frequency and are commonly used off-label. Topiramate reduces binge frequency and promotes weight loss but is limited in adolescents by cognitive side effects including word-finding difficulty and paresthesias. Bupropion is contraindicated in BN because purging-related electrolyte abnormalities lower the seizure threshold.

<image>A comparison chart of bulimia nervosa vs. binge eating disorder in adolescents. Categories: diagnostic criteria (both have binge eating, but BN has compensatory behaviors while BED does not), typical weight status (BN: normal to overweight; BED: overweight to obese), body image (both have disturbance but BN more driven by weight/shape), gender ratio (BN more female; BED more equal), key comorbidities, and first-line treatments (CBT-E for both; FBT-BN for BN; lisdexamfetamine for BED).</image>

<image>A diagram of the binge-purge cycle in bulimia nervosa. Show a circular pathway: dietary restriction/rigid food rules leads to hunger and deprivation, which leads to binge eating (loss of control, large food intake), which leads to guilt and shame, which leads to compensatory behavior (vomiting, laxatives, excessive exercise), which leads to temporary relief, which reinforces dietary restriction. Show where CBT-E interventions target each part of the cycle: regular eating breaks the restriction-binge link, cognitive restructuring addresses guilt and body image, eliminating purging reduces the reinforcement of the cycle.</image>

<image>A medical complications infographic for bulimia nervosa, organized by body system. Include: oral (dental erosion, parotid enlargement), esophageal (Mallory-Weiss tears, esophagitis), cardiac (arrhythmia from hypokalemia), metabolic (metabolic alkalosis from vomiting, metabolic acidosis from laxatives), dermatological (Russell sign on knuckles), renal (dehydration, electrolyte imbalance), endocrine (menstrual irregularities). Show physical exam findings that should raise suspicion for BN.</image>

Clinical Pearls

BN and BED are under-recognized in adolescents, and clinicians should screen proactively, especially in patients presenting with depression, self-harm, impulsivity, or weight concerns. Normal weight does not rule out BN, as most adolescents with the disorder are normal weight or overweight. Dietary restriction and rigid food rules perpetuate binge eating, and establishing regular eating is one of the most important early interventions. Russell sign (calluses on the knuckles) and dental erosion are physical exam clues to BN but may be absent. Bupropion is contraindicated in BN because purging-related electrolyte disturbances lower the seizure threshold. Fluoxetine at 60 mg/day — higher than the typical antidepressant dose — is the recommended pharmacotherapy for BN. Lisdexamfetamine is effective for BED but carries stimulant-related abuse potential and should be used cautiously in adolescents. Loss of control eating, even without objectively large binge episodes, is clinically significant in children and adolescents and predicts future BED development.

References

• Fairburn, C.G. (2008). Cognitive Behavior Therapy and Eating Disorders. New York: Guilford Press.
• Le Grange, D. et al. (2007). Randomized clinical trial of family-based treatment and supportive psychotherapy for adolescent bulimia nervosa. Archives of General Psychiatry, 64(9), 1049-1056.
• McElroy, S.L. et al. (2015). Lisdexamfetamine dimesylate for adults with moderate to severe binge eating disorder. JAMA Psychiatry, 72(3), 235-246.
• Swanson, S.A. et al. (2011). Prevalence and correlates of eating disorders in adolescents: results from the NCS-A. Archives of General Psychiatry, 68(7), 714-723.
• Goldschmidt, A.B. et al. (2008). Loss of control eating in overweight children seeking treatment for obesity. Behaviour Research and Therapy, 46(10), 1105-1110.
• NICE (2017). Eating disorders: recognition and treatment. NICE guideline NG69.

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