Bulimia Nervosa: Binge-Purge Cycle, Health Consequences & Treatment

Bulimia nervosa (BN) is characterized by recurrent episodes of:

1. Binge eating: Consuming objectively large amount in discrete period (≤2 hrs) with loss of control.
2. Compensatory behaviors to prevent weight gain: self-induced vomiting (most common), laxative/diuretic/enema misuse, fasting, excessive exercise.
3. Occurring ≥1×/week for 3 months.
4. Self-evaluation unduly influenced by body shape/weight.

The Vicious Cycle

Restriction → hunger/urge → binge → guilt/shame → purge → temporary relief → renewed restriction.

Medical Complications

• Electrolytes: Hypokalemia, hypochloremia, metabolic alkalosis (vomiting); hypokalemia, metabolic acidosis (laxatives). → Arrhythmia, sudden death risk.
• GI: Esophagitis, Mallory-Weiss tears, Boerhaave syndrome (esophageal rupture), gastroparesis, rectal prolapse, cathartic colon.
• Dental: Perimolysis (enamel erosion lingual surfaces), caries, salivary gland enlargement (sialadenosis).
• Endocrine: Menstrual irregularities, bone loss.
• Psychiatric: Depression, anxiety, substance use, impulsivity, suicide risk.

Evidence-Based Treatment

• CBT-E (Enhanced Cognitive Behavioral Therapy): Gold standard. Targets dietary restraint, cognitive distortions, mood intolerance.
• FBT-BN: Family-based for adolescents.
• SSRIs (fluoxetine 60 mg): Only FDA-approved med for BN; reduces binge/purge frequency.
• Medical stabilization for electrolyte abnormalities, cardiac monitoring.
• Nutritional counseling: Mechanical eating (3 meals + 2–3 snacks), exposure to fear foods.

Recovery rates ~50% at 5–10 years. Early intervention improves prognosis. Multidisciplinary team essential.