Diagnosis: Anorexia Nervosa, Binge-Eating/Purging Type
A patient who restricts eating AND purges meets diagnostic criteria for Anorexia Nervosa, Binge-Eating/Purging Type, regardless of whether objective binge episodes occur. The critical distinction is that this patient restricts food intake (characteristic of anorexia nervosa) while also engaging in purging behaviors 1.
Diagnostic Algorithm
The diagnosis hinges on three key features:
- Restrictive eating pattern - The patient limits caloric intake
- Purging behaviors - Self-induced vomiting, laxative abuse, or other compensatory methods
- Weight status - Must meet low body weight criteria for anorexia nervosa (typically BMI <18.5 in adults or <5th percentile in adolescents)
The presence of purging behavior is the critical subtyping factor, not whether objective binge episodes occur 2. Research demonstrates that anorexia nervosa patients who purge display significantly more psychopathology than pure restrictors, regardless of binge eating 2. This makes purging behavior itself—not binge eating—the most clinically relevant marker for subclassification.
Key Diagnostic Distinctions
If the patient has LOW body weight + restricts + purges:
- Diagnosis: Anorexia Nervosa, Binge-Eating/Purging Type
- This applies even without objective binge episodes
- Purging may follow subjective binges or normal eating
If the patient has NORMAL/HIGH body weight + restricts + purges:
- Diagnosis: Bulimia Nervosa (if objective binges occur)
- Diagnosis: Purging Disorder (if purging without objective binges)
Essential Clinical Assessment
Per APA guidelines, your initial evaluation must quantify 1:
- Frequency and intensity of dietary restriction
- Specific purging methods (vomiting, laxatives, diuretics, enemas)
- Time spent on compensatory behaviors
- Weight history (current, maximum, minimum BMI)
- Preoccupation with food, weight, and body shape
Critical Medical Workup
Immediate medical assessment is mandatory 1:
- Vital signs: Temperature, resting heart rate, blood pressure with orthostatics
- ECG: Required for all patients with restrictive eating AND severe purging due to QTc prolongation risk
- Labs: CBC, comprehensive metabolic panel (electrolytes, liver enzymes, renal function)
Common Pitfall
Do not wait for "classic" anorexia nervosa appearance. Patients may not appear severely underweight but still have dangerous electrolyte abnormalities and cardiac complications from purging 3.
Prognostic Implications
The presence of purging behavior is a negative prognostic factor 4. Patients with anorexia nervosa who purge have:
- More severe psychopathology than pure restrictors
- Higher rates of comorbid personality disorders (borderline, avoidant)
- Greater depression and obsessive symptoms 5
- Less favorable treatment outcomes compared to restricting-only anorexia 4
Treatment Priorities
Based on the diagnosis of Anorexia Nervosa, Binge-Eating/Purging Type 1:
For adults:
- Eating disorder-focused psychotherapy addressing restriction, purging, and weight restoration
- Normalize eating patterns and eliminate compensatory behaviors
- Set individualized weekly weight gain goals
For adolescents/emerging adults:
- Family-based treatment (FBT) as first-line
- Caregiver education focused on normalizing eating and stopping purging behaviors
The combination of restriction and purging creates heightened medical risk requiring coordinated multidisciplinary care with medical, psychiatric, psychological, and nutritional expertise 1.