Managing Eating Disorders

Guides eating disorder assessment with medical stability criteria, APA Practice Guidelines for Treatment of Eating Disorders, and level-of-care determination using APA and AACAP placement criteria.

Why This Skill Exists

Eating disorders have the highest mortality rate of any psychiatric illness, with anorexia nervosa carrying a standardized mortality ratio of 5.86 — six times the expected death rate. Medical complications including cardiac arrhythmias, electrolyte derangements, refeeding syndrome, and organ failure require coordinated psychiatric-medical management. The APA Practice Guidelines for the Treatment of Patients with Eating Disorders (Third Edition) establish evidence-based standards for assessment, medical stabilization, nutritional rehabilitation, psychotherapy, and pharmacotherapy.

Underrecognition remains a critical problem — average time from symptom onset to treatment is 5-7 years. Males, older adults, ethnic minorities, and individuals with atypical presentations (normal or higher weight) are systematically underdiagnosed. Level-of-care decisions must integrate psychiatric severity, medical instability, and nutritional status using validated criteria, not clinical impression alone.

Checkpoint A: Pre-Draft Intake (Mandatory)

What is the suspected or confirmed eating disorder diagnosis? (anorexia nervosa restricting type, AN binge-purge type, bulimia nervosa, binge eating disorder, ARFID, other specified/unspecified) — default: assess at intake
What is the patient's current weight, height, and BMI? — default: obtain vital signs
What is the patient's weight history? (highest, lowest, premorbid) — default: obtain
Are there signs of medical instability? (bradycardia, orthostatic hypotension, electrolyte abnormalities, hypothermia) — default: assess immediately
What is the purging method and frequency, if applicable? (vomiting, laxatives, diuretics, exercise, insulin omission) — default: assess
Is the patient currently in treatment? If so, what level of care? — default: assess
Does the patient have co-occurring psychiatric conditions? (depression, anxiety, OCD, PTSD, SUD, personality disorder) — default: screen
Is the patient medically cleared or is medical clearance needed? — default: obtain labs and ECG

Documents to Request

Complete metabolic panel (Na, K, Cl, CO2, BUN, Cr, glucose, Ca, Mg, Phos)
CBC with differential
Hepatic function panel
Thyroid panel (TSH, free T4)
ECG (12-lead)
Vital signs including orthostatic blood pressure and heart rate
Amylase and lipase (elevated amylase suggests purging)
Urinalysis (specific gravity for hydration status, laxative screen)
DEXA scan if amenorrhea >6 months or low BMI >6 months
Prior treatment records including weight charts, meal plans, treatment summaries
Nutritional assessment from registered dietitian
Dental records if purging (enamel erosion documentation)

Step 1: Diagnostic Assessment

DSM-5-TR Eating Disorder Diagnoses

Anorexia Nervosa (F50.0x):

Criterion A: Restriction of energy intake leading to significantly low body weight (BMI <18.5 in adults; in children, failure to make expected weight gain)
Criterion B: Intense fear of gaining weight or persistent behavior interfering with weight gain
Criterion C: Disturbance in body weight/shape experience, undue influence on self-evaluation, or persistent lack of recognition of seriousness
Subtypes: Restricting (F50.01) vs. Binge-eating/purging (F50.02)
Severity by BMI: Mild ≥17, Moderate 16-16.99, Severe 15-15.99, Extreme <15

Bulimia Nervosa (F50.2):

Recurrent binge eating episodes (large amount in discrete period with sense of loss of control)
Recurrent compensatory behaviors (vomiting, laxatives, diuretics, fasting, excessive exercise)
Binge eating and compensatory behaviors occur at least once per week for 3 months
Self-evaluation unduly influenced by body shape and weight
Severity: Mild 1-3/week, Moderate 4-7, Severe 8-13, Extreme ≥14 compensatory episodes/week

Binge Eating Disorder (F50.81):

Recurrent binge episodes (at least once/week for 3 months)
Marked distress regarding binge eating
Three or more of: eating rapidly, eating until uncomfortably full, eating large amounts when not hungry, eating alone due to embarrassment, feeling disgusted/depressed/guilty after
NOT associated with regular compensatory behaviors

Avoidant/Restrictive Food Intake Disorder (ARFID, F50.82):

Eating disturbance leading to persistent failure to meet nutritional/energy needs
NOT better explained by lack of food, cultural practice, concurrent medical condition, or another mental disorder
NOT associated with body image disturbance

Step 2: Medical Stability Assessment

Assess for medical emergencies requiring immediate stabilization:

Criteria for Medical Hospitalization (APA/AACAP):

Heart rate <50 bpm (adults) or <40 bpm
Blood pressure <90/60 mmHg
Orthostatic changes: HR increase >20 bpm or BP drop >20/10 mmHg on standing
Temperature <97.0°F (36.1°C)
Potassium <3.2 mEq/L or other dangerous electrolyte abnormality
Glucose <60 mg/dL
BMI <15 (adults) or <75% median BMI (adolescents)
Dehydration
ECG abnormalities: prolonged QTc >450ms, arrhythmia, ST changes
Acute medical complications of purging (Mallory-Weiss tear, esophageal rupture, aspiration)
Syncope
Seizures
Organ failure markers

Refeeding Syndrome Risk Assessment: Refeeding syndrome is the most dangerous medical complication of nutritional rehabilitation and can be fatal. High-risk patients include:

BMI <16 or weight loss >15% in 3-6 months
Little or no nutritional intake for >10 days
Low pre-feeding phosphate, potassium, or magnesium
History of alcohol misuse, chemotherapy, or insulin use

Monitor: Phosphate, potassium, magnesium, calcium daily during first 7-10 days of refeeding. Start caloric intake conservatively (1,200-1,500 kcal/day in severe cases) and advance slowly with electrolyte supplementation.

Step 3: Level-of-Care Determination

Inpatient Medical: Medical instability meeting any criteria above. Primary focus: medical stabilization, electrolyte correction, cardiac monitoring, refeeding initiation.

Inpatient Psychiatric: Medically stable but: suicidal ideation with plan/intent, severe malnutrition requiring structured refeeding, failure of lower levels of care, inability to maintain nutritional intake in less structured settings, severe co-occurring psychiatric symptoms.

Residential Treatment: Medically stable, BMI typically ≥15, able to participate in programming, requires 24-hour structure for meals and symptom management, failure of PHP/IOP.

Partial Hospitalization (PHP): Medically stable, BMI typically >16, can be safe overnight, needs structured eating during the day (typically 3 meals + 2-3 snacks supervised).

Intensive Outpatient (IOP): Medically stable, weight restoration progressing, needs support but can manage most meals independently.

Outpatient: Medically stable, weight stable or progressing, can manage meals with minimal professional support, working on relapse prevention and body image issues.

Step 4: Treatment Interventions

Nutritional Rehabilitation:

Target weight restoration of 1-2 lbs/week for inpatient, 0.5-1 lb/week for outpatient
Registered dietitian to develop individualized meal plan
Monitor weight (gown weight, after voiding, before meals — consistent conditions)
Supervise meals and post-meal periods (minimum 30-60 minutes post-meal to prevent purging)
Address refeeding syndrome risk with electrolyte monitoring and supplementation

Psychotherapy (Evidence-Based):

Anorexia Nervosa Adults: CBT-E (Enhanced CBT), SSCM (Specialist Supportive Clinical Management), or psychodynamic therapy. No single therapy has strong evidence superiority for AN.
Anorexia Nervosa Adolescents: FBT (Family-Based Treatment / Maudsley Approach) is the gold-standard first-line treatment
Bulimia Nervosa: CBT-BN (first-line), IPT (interpersonal therapy) as alternative
Binge Eating Disorder: CBT-BN adapted for BED, IPT, DBT

Pharmacotherapy:

AN: No medication has FDA approval. SSRIs NOT effective for acute weight restoration. Consider fluoxetine for relapse prevention AFTER weight restoration.
BN: Fluoxetine 60mg/day (only FDA-approved medication for BN). Topiramate off-label (caution: appetite suppression).
BED: Lisdexamfetamine (Vyvanse) 50-70mg/day (FDA approved). Topiramate off-label. SSRIs may reduce binge frequency.
Do NOT prescribe bupropion in patients with purging behaviors (seizure risk).

Step 5: Ongoing Monitoring and Relapse Prevention

Weekly weight monitoring (outpatient), daily (inpatient/residential)
Monthly labs (CMP, phosphate, magnesium) during active treatment
ECG monitoring if cardiac symptoms, electrolyte abnormalities, or medication changes
DEXA scan annually if amenorrhea persists or BMI <18.5
Dental referral for patients with purging history
Monitor for exercise compulsion (which may replace other compensatory behaviors)
Develop relapse prevention plan identifying triggers, early warning signs, and intervention strategies
Family involvement in treatment planning (essential for adolescents, strongly recommended for adults)

Checkpoint B: Post-Draft Alignment (Mandatory)

Is the DSM-5-TR diagnosis documented with specific criteria met and severity specifier?
Is the medical stability assessment documented with all relevant vital signs and lab values?
Is the level-of-care recommendation supported by specific clinical criteria (not just clinical impression)?
Are evidence-based treatments selected for the specific diagnosis?
Is the refeeding risk assessment documented for patients requiring nutritional rehabilitation?

Quality Audit

[ ] DSM-5-TR eating disorder diagnosis with severity specifier documented
[ ] Weight, BMI, and weight history documented
[ ] Vital signs including orthostatics obtained and documented
[ ] Laboratory panel including electrolytes, CBC, and metabolic panel reviewed
[ ] ECG obtained and interpreted
[ ] Medical stability criteria assessed systematically
[ ] Refeeding syndrome risk assessment completed
[ ] Level-of-care determination documented with supporting criteria
[ ] Purging behaviors assessed with specific method, frequency, and duration
[ ] Co-occurring psychiatric diagnoses screened and documented
[ ] Suicide risk assessment completed (elevated risk in AN)
[ ] Evidence-based psychotherapy selected for specific diagnosis
[ ] Medication decisions documented with rationale (including decision NOT to medicate in AN)
[ ] Nutritional rehabilitation goals documented with target weight and rate
[ ] Family involvement plan documented

Guidelines

Never prescribe bupropion to patients with active purging behaviors — seizure risk is significantly elevated and this is a contraindication per FDA labeling.
Always obtain orthostatic vital signs in eating disorder assessments — bradycardia and orthostatic hypotension are the most common indicators of medical instability.
Monitor phosphate levels during refeeding — hypophosphatemia is the hallmark of refeeding syndrome and can cause cardiac arrest, respiratory failure, and death if untreated.
Do not rely on BMI alone for severity assessment — patients with significant weight loss from a higher baseline may be medically unstable at a "normal" BMI (atypical anorexia nervosa).
For adolescents with anorexia nervosa, FBT (Family-Based Treatment) is the first-line intervention — individual therapy alone is less effective than family-based approaches in this population.
Screen all eating disorder patients for suicide risk — anorexia nervosa has one of the highest suicide rates of any psychiatric diagnosis, and completed suicide accounts for approximately 20% of AN deaths.
Involve a registered dietitian as part of the multidisciplinary team — medication management alone is insufficient for eating disorders.