The aetiology of eating disorders isn’t fully understood, but we know that there is not a single definitive cause for the development of bulimia.
Numerous genetic, social and psychological factors often play a role in the development of an eating disorder.
There are often numerous factors that contribute to a person developing bulimia.
Genetic risk factors for bulimia include:
Family history of eating disorders
Family history of mental illness
Family history of impulse control disorders
Psychosocial risk factors for bulimia include:4
Prior mental health diagnosis
History of abuse or trauma
Having a career or hobby dependent on appearance
History of engaging in restricting and bingeing cycles
Typical symptoms of bulimia nervosa include:4
Engaging in binge eating behaviours
Distress over body image
Frequent bathroom trips following meals
Uncomfortable eating food in the presence of others
Mood disturbance: irritability, depression, suicidal ideation and self-harm behaviours
The term ‘purging’ is used in relation to bulimia. This refers to an individual engaging in binge eating behaviours followed by ‘purging’ behaviours such as self-induced vomiting, strenuous exercise, using laxatives, enemas or diuretics to counteract their food binge.4
Other important areas to cover in the history include:
Past medical history: including any past psychiatric diagnoses or admissions and any medical conditions (particularly of diabetes)
Drug history: regular and over the counter medicine (e.g. laxatives)
Social history: social support networks, family circumstances, alcohol and drug use
It is important to perform a risk assessment in all patients with a suspected eating disorder, as it is with any mental health disorder.
This includes determining their risk of self-harm, suicidal actions or self-neglect. It is common for eating disorders to co-exist with other mental health disorders such as depression and anxiety.
Typical clinical findings in bulimia nervosa may include:
People with bulimia often have a normal body weight, often accompanied by weight fluctuations
Swollen salivary glands
Gastro-oesophageal reflux and irritation
Alkalosis: due to loss of hydrochloric acid from the stomach
Russel’s sign: calluses on the knuckles where they have scraped against the teeth
Differential diagnoses for bulimia include:
Anorexia nervosa: patients with anorexia often present with a severely low BMI, unlike in bulimia where the BMI is usually normal or raised. In anorexia, there is a restriction of energy intake, whereas in bulimia recurrent episodes of binge eating with compensatory mechanisms are evident.
Urinalysis: may show ketones if the patient has co-morbid diabetes mellitus. Some patients may skip insulin to control their weight. This is often referred to as ‘diabulimia’.
ECG: important to perform if there is a severe deficiency in potassium or magnesium. Features of hypokalaemia include increased P wave amplitude, prolonged PR interval, ST depression and T wave flattening/inversion and prominent U waves.
Relevant laboratory investigations include:
Urea & electrolytes: these may show hypokalaemia and/or increased creatinine. Elevated bicarbonate usually indicates alkalosis due to loss of gastric acid.
Magnesium: may be low
Full blood count: may show anaemia
Liver function tests: may be abnormal as excess exercise can elevate aminotransferases
The ICD-11 criteria for bulimia include the following features:1
Preoccupation with controlling body weight
Repeated bouts of overeating
Compensatory behaviours after overeating, including self-induced vomiting, using laxatives and excessive exercise
These binge eating and compensatory behaviours usually occur at least once weekly for three months.2
As with all mental health conditions, it is helpful to think of management as a biopsychosocial approach, this helps to ensure that management is holistic.
Selective serotonin-reuptake inhibitors (SSRIs) are used for the pharmacological management of bulimia. Fluoxetine is typically used first-line, followed by sertraline if this is poorly tolerated.
These may be used when cognitive behaviour therapy (CBT) isn’t available or when it has been tried and the patient hasn’t seen any improvement.
The medications should be given at a time of day when they are unlikely to be purged.2
SSRIs are also useful in the case of comorbid disorders (e.g. depression and anxiety).
Cognitive behavioural therapy is seen as the optimal first-line treatment for bulimia. This is offered alongside nutritional and meal support (delivered by a trained dietician).
Children with bulimia should be offered bulimia nervosa focused family therapy.2
It is important to provide education about bulimia to the patient and their family. Online resources such as the Beat website are useful sources of patient information and support.
Diabetes and bulimia
Patients with diabetes need input from an endocrinologist with respect to their glycemic control and insulin management. Admission to hospital may be required.2
Complications of bulimia include:4
Irregular menstrual cycles and fertility issues
Mental health conditions such as depression and anxiety
Heart issues including arrhythmias, heart attacks or failure and cardiomyopathy
Dr William Davies
Psychiatry Registrar (ST6)
Dr Chris Jefferies
ICD-11. Bulimia nervosa. (2021). Available from: [LINK]
BMJ Best Practice. Bulimia nervosa. (2021). Available from: [LINK]
NICE CKS. Eating disorders: How common is it?. (2019). Available from [LINK]
Eating Disorder Hope. What is bulimia: Symptoms, Complications and Causes. Available from: [LINK]