Table of contents

Anorexia nervosa

What's new

Updated 2023 APA, 2022 USPSTF, 2022 SIGN, and 2021 CPG guidelines for the diagnosis and management of anorexia nervosa.



Anorexia nervosa is a psychiatric condition characterized by severe weight loss and secondary problems associated with malnutrition, often developing in adolescence during the peripubertal period.
The exact causes of anorexia nervosa are unknown, but it is believed to be a result of a complex interplay of genetic, environmental, and psychological factors. Genetic factors influence risk, psychosocial and interpersonal factors can trigger onset, and changes in neural networks can sustain the illness.
The lifetime prevalence of anorexia nervosa by age 19 years is reported to be 1.7% in females and only 0.1% in males.
Disease course
Clinically, anorexia nervosa manifests physically through extreme weight loss, amenorrhea, and the growth of fine, downy hair called lanugo. Psychologically, patients with anorexia nervosa often exhibit body dysmorphia and obsessive behavior around food, including restriction methods and a relentless preoccupation with dieting and weight loss.
Prognosis and risk of recurrence
The prognosis of anorexia nervosa is variable, with outcomes ranging from full recovery to chronic illness. Some patients may recover completely, while others may experience a relapsing and remitting course, and some may remain chronically ill.


Key sources

The following summarized guidelines for the evaluation and management of anorexia nervosa are prepared by our editorial team based on guidelines from the American Psychiatric Association (APA 2023), the The Scottish Intercollegiate Guidelines Network (SIGN 2022), the U.S. Preventive Services Task Force (USPSTF 2022), the Canadian Practice Guidelines (CPG 2021,2020), the German Society for Psychiatry, Psychotherapy and Psychosomatics (DGPPN 2019), ...
Show more

Screening and diagnosis

Indications for screening: as per APA 2023 guidelines, screen for the presence of an eating disorder as part of an initial psychiatric evaluation.
Create free account

Diagnostic investigations

Initial evaluation: as per APA 2023 guidelines, assess the following during the initial evaluation of patients with a possible eating disorder:
height and weight history (maximum and minimum weight, recent weight changes)
presence of, patterns in, and changes in restrictive eating, food avoidance, binge eating, and other eating-related behaviors (rumination, regurgitation, chewing, and spitting)
patterns and changes in food repertoire (breadth of food variety, narrowing or elimination of food groups)
presence of, patterns in, and changes in compensatory and other weight control behaviors, including dietary restriction, compulsive or driven exercise, purging behaviors (laxative use, self-induced vomiting), and use of medication to manipulate weight
percentage of time preoccupied with food, weight, and body shape
prior treatment and response to treatment for an eating disorder
psychosocial impairment secondary to eating or body image concerns or behaviors
family history of eating disorders, other psychiatric illnesses, and other medical conditions (obesity, IBD, diabetes mellitus).
Show 2 more

More topics in this section

  • Laboratory tests

  • ECG

  • Screening for comorbidities

Medical management

Multidisciplinary care: as per APA 2023 guidelines, provide a documented, comprehensive, culturally appropriate, and person-centered treatment plan incorporating medical, psychiatric, psychological, and nutritional expertise, commonly via a coordinated multidisciplinary team, in patients with an eating disorder.

More topics in this section

  • Pharmacotherapy (general principles)

  • Pharmacotherapy (antipsychotics)

  • Pharmacotherapy (antidepressants)

Inpatient care

Indications for hospitalization: as per CPG 2020 guidelines, provide the least intensive treatment environment (such as family-based treatment or day treatment versus lengthy hospitalizations) especially in pediatric and adolescent patients with anorexia nervosa requiring a first admission to hospital and/or with a duration of illness < 3 years.

Nonpharmacologic interventions

As per APA 2023 guidelines:
Offer eating disorder-focused psychotherapy including normalizing eating and weight control behaviors, restoring weight, and addressing psychological aspects of the disorder (such as fear of weight gain and body image disturbance) in adult patients with anorexia nervosa.
Offer eating disorder-focused family-based treatment including caregiver education aimed at normalizing eating and weight control behaviors and restoring weight in adolescent and emerging adult patients with anorexia nervosa having an involved caregiver.

More topics in this section

  • Technology-based interventions

  • Nutritional management

  • Exercise programs

  • Yoga

Specific circumstances

Pregnant patients: as per SIGN 2022 guidelines, elicit history of current or past history of eating disorders in females during pregnancy and postnatal period, recognizing the potential barriers for disclosure.
Show 13 more

More topics in this section

  • Patients with T1DM

  • Patients with osteopenia/osteoporosis