# Eating Disorders in Adolescents > Eating disorders in adolescents for NEET-PG Paediatrics covering anorexia and bulimia nervosa, refeeding syndrome and family-based treatment. - Canonical URL: https://prepelephant.com/topics/neet-pg/paediatrics/eating-disorders-in-adolescents - Exam / course: NEET-PG · Subject: Paediatrics - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-14 - Last updated: 2026-10-14 - Reference basis: Nelson Textbook of Pediatrics; Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition - How to cite: "Eating Disorders in Adolescents", PrepElephant, https://prepelephant.com/topics/neet-pg/paediatrics/eating-disorders-in-adolescents ## Direct answer Anorexia nervosa is restriction of intake that leads to low body weight, with an intense fear of weight gain and a disturbed body image, while bulimia nervosa involves recurrent binge eating followed by compensatory behaviour at near-normal weight. The main medical dangers are bradycardia, electrolyte disturbance and refeeding syndrome. Family-based treatment is first-line for adolescent anorexia nervosa, and enhanced cognitive behavioural therapy is first-line for bulimia nervosa. ## What you must remember - **Anorexia nervosa:** Restriction, low body weight, intense fear of weight gain and disturbed body image. - **Subtypes:** Restricting type, and binge-purging type in which vomiting or laxative misuse occurs. - **Bulimia nervosa:** Recurrent binge eating and compensatory behaviour at least once a week for three months, usually at normal weight. - **Amenorrhoea:** Not a required DSM-5 criterion for anorexia, so its absence does not rule out the disorder. - **Bradycardia and hypothermia:** Serious cardiovascular signs in anorexia, which may need admission. - **Refeeding syndrome:** Falls in phosphate, potassium and magnesium when feeding restarts, with risk of cardiac and respiratory failure. - **Family-based treatment:** First-line for adolescent anorexia, with parents supporting weight restoration. - **CBT-E:** Enhanced cognitive behavioural therapy, first-line for bulimia nervosa in adults and older adolescents. ## A stepwise pathway from medical stability to recovery Severe anorexia nervosa needs medical stability before psychological work can progress. The steps below set out a practical sequence for an adolescent with low weight. 1. **Assess medical stability:** Check heart rate, blood pressure, temperature, orthostatic changes, electrolytes and blood glucose. 2. **Decide on admission:** Admit for severe bradycardia, electrolyte disturbance, syncope, rapid weight loss or failed outpatient care. 3. **Identify refeeding risk:** Look for very low intake or significant weight loss before feeding starts, as these patients are most vulnerable. 4. **Start feeding cautiously:** Begin with modest intake and increase gradually, checking phosphate, potassium and magnesium frequently in the first days. 5. **Replace electrolytes:** Correct hypophosphataemia, hypokalaemia and hypomagnesaemia before and during refeeding. 6. **Start psychological treatment:** Use family-based treatment for adolescents, with parents supporting weight restoration. 7. **Plan relapse prevention:** Track weight, menstrual function and bone health, since osteopenia and growth delay can persist. Medical stability and psychological care run in parallel, and the team should agree weight goals with the family from the start. Relapse is common, so follow-up continues well after weight is restored. ## Where the exam tries to catch you Eating disorder questions often test the amenorrhoea criterion, the refeeding risk and the first-line treatment for each disorder. - **Trap:** Requiring amenorrhoea before diagnosing anorexia nervosa. — **Correct:** DSM-5 dropped that criterion, so a regular menstrual cycle does not exclude anorexia. - **Trap:** Starting full calories at once in a severely underweight teen. — **Correct:** Feeding starts cautiously because refeeding syndrome can cause fatal cardiac and respiratory complications. - **Trap:** Using fluoxetine to restore weight in anorexia nervosa. — **Correct:** Medication has no proven role in weight restoration, and psychotherapy is the mainstay. - **Trap:** Excluding bulimia nervosa because the child is not underweight. — **Correct:** Bulimia nervosa usually occurs at normal weight, so body weight does not identify it. ## Frequently asked questions ### What is the core difference between anorexia nervosa and bulimia nervosa? Anorexia nervosa involves restriction that produces low body weight and an intense fear of gaining weight. Bulimia nervosa involves recurrent binge eating followed by compensatory behaviour, and it usually occurs at near-normal weight. Body weight alone therefore does not identify bulimia nervosa. ### Why is refeeding syndrome a risk in adolescents with anorexia nervosa? Refeeding syndrome is a risk in adolescents with anorexia nervosa because restarting food can rapidly lower phosphate, potassium and magnesium. This can cause cardiac arrhythmia, heart failure and respiratory failure. Electrolytes are therefore checked before feeding and monitored closely in the first days. ### What is family-based treatment for adolescent anorexia nervosa? Family-based treatment is the first-line psychological treatment for adolescent anorexia nervosa, in which parents take an active role in restoring the young person's weight. It is delivered in structured phases that gradually return control of eating to the adolescent. Its evidence base is strongest in adolescents. ### Which psychological treatment is first-line for bulimia nervosa? Enhanced cognitive behavioural therapy, known as CBT-E, is the first-line psychological treatment for bulimia nervosa in adults and older adolescents. It targets binge eating, purging and over-evaluation of weight and shape. Fluoxetine may be used alongside therapy in some cases.