Bulimia Nervosa

Bulimia Nervosa involves recurrent episodes of binge eating — consuming an unusually large amount of food with a sense of loss of control — followed by compensatory behaviors intended to prevent weight gain, alongside self-evaluation unduly influenced by body shape and weight. Unlike anorexia, body weight in bulimia is often within or above the normal range, which can make the illness less visually apparent, but it carries serious, sometimes life-threatening medical risks regardless of weight.

Bulimia Nervosa is defined by recurrent episodes of binge eating — eating, within a discrete period, an amount of food definitely larger than most people would eat in similar circumstances, with a sense of lack of control — together with recurrent inappropriate compensatory behaviors to prevent weight gain (self-induced vomiting, misuse of laxatives or diuretics, fasting, or excessive exercise). Both behaviors must occur, on average, at least once a week for three months, alongside self-evaluation unduly influenced by body shape and weight, and not occurring exclusively during episodes of anorexia nervosa.

Bulimia arises from genetic vulnerability combined with a history of dieting — restrictive dieting is a well-established trigger that often precedes binge eating episodes. Binge eating can serve as a way of coping with or numbing difficult emotions, with the subsequent compensatory behavior driven by shame and fear of weight gain. Sociocultural pressure around thinness interacts with this underlying vulnerability, and impulsivity as a temperamental trait is also implicated.

• Family history of eating disorders or mood disorders
• History of dieting or weight-based teasing
• A perfectionistic or impulsive temperament
• History of trauma or abuse
• Co-occurring depression, anxiety, or substance use
• Participation in weight-focused activities or professions

Bulimia involves altered function in brain reward and impulse-control circuits, with binge episodes potentially reflecting a dysregulated reward response to food, particularly after periods of restriction, which physiologically increases the drive to eat. Serotonin system dysregulation is implicated, consistent with the effectiveness of SSRIs in treatment. The alternating pattern of restriction and overconsumption itself creates a physiological cycle that reinforces the disorder over time.

• Recurrent binge eating episodes with a sense of loss of control
• Recurrent compensatory behaviors: self-induced vomiting, laxative or diuretic misuse, fasting, or excessive exercise
• Preoccupation with body shape and weight
• Secrecy and shame around eating behaviors
• Dental erosion from repeated vomiting
• Swelling of the salivary glands
• Calluses on the back of the hand from inducing vomiting
• Electrolyte disturbances, sore throat, and irregular menstrual periods

• Recurrent binge eating episodes with a sense of loss of control
• Recurrent inappropriate compensatory behaviors to prevent weight gain
• Both occurring, on average, at least once a week for 3 months
• Self-evaluation unduly influenced by body shape and weight
• Not occurring exclusively during episodes of anorexia nervosa

Conditions a psychiatrist will consider and rule out before confirming this diagnosis:

Anorexia Nervosa, binge-eating/purging type

Distinguished by significantly low body weight, which is not typically present in bulimia.

Binge Eating Disorder

Binge eating occurs without the recurrent compensatory behaviors central to bulimia.

Major Depressive Disorder with atypical features

Increased eating can occur, but without the specific binge-purge pattern and body image disturbance.

Borderline Personality Disorder

Impulsive eating behavior can occur as part of broader impulsivity, though bulimia is diagnosed based on the specific pattern meeting full criteria.

• Clinical interview and detailed eating and behavior history, requiring sensitive, non-judgmental inquiry given the shame and secrecy commonly involved
• Physical examination: dental exam, salivary gland assessment, hand calluses
• Electrolyte testing, critical given the risk of dangerous abnormalities, particularly potassium, from vomiting or laxative misuse
• ECG if electrolyte disturbance is significant
• Screening for co-occurring depression, anxiety, and substance use

Cognitive Behavioral Therapy for Eating Disorders (CBT-E) is the first-line, best-evidenced treatment. SSRIs, particularly fluoxetine, which has specific approval for bulimia, can reduce binge-purge frequency and are often used alongside therapy — a combination is often more effective than either alone.

Fluoxetine

Specifically approved for bulimia nervosa, often at a higher dose than used for depression.

Other SSRIs

May also be used.

Bupropion is specifically avoided

Given an increased seizure risk in people with bulimia.

Cognitive Behavioral Therapy for Eating Disorders (CBT-E)

Addresses the interconnected cycle of restriction, bingeing, and compensatory behavior, alongside body image concerns.

Interpersonal Therapy

An effective alternative, particularly when relationship difficulties contribute to the pattern.

Dialectical Behavior Therapy skills

Useful for the emotion regulation component often driving binge eating.

Family-Based Treatment

Adapted for adolescents with bulimia.

• Establish regular, structured eating patterns, since skipping meals or overly restrictive eating increases the likelihood of subsequent binge episodes
• Avoid rigid food rules
• Build alternative coping strategies for difficult emotions that don't involve food
• Reduce exposure to diet culture and body-focused social media content
• Work with a dietitian experienced in eating disorders

With CBT-E and/or medication, a substantial proportion of people achieve significant reduction or full remission of binge-purge behaviors. Untreated, bulimia can lead to serious medical complications, particularly from electrolyte disturbances, and tends to persist chronically. Earlier treatment is associated with better outcomes.

• Early intervention for restrictive dieting patterns before they progress to a binge-purge cycle
• Addressing weight-based teasing or bullying
• Building healthy coping strategies for emotional distress that don't center on food
• Media literacy around unrealistic body standards

Approach the person with compassion rather than shock or disgust if compensatory behaviors are discovered, given the significant shame typically involved. Avoid commenting on weight or specific foods, and support professional treatment engagement. Be aware of physical warning signs — frequent bathroom trips after meals, disappearing food, dental problems — without becoming a 'food police,' which can worsen secrecy. Treat any indication of severe electrolyte disturbance (weakness, palpitations, fainting) as a medical emergency.

1. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, 5th Edition, Text Revision (DSM-5-TR).
2. World Health Organization. International Classification of Diseases, 11th Revision (ICD-11).
3. National Institute for Health and Care Excellence (NICE). Eating disorders: recognition and treatment.