Physicians may diagnose bulimia nervosa based on the patient’s symptoms and eating habits: binge eating and purging cycles that occur at least twice a week for a period of three months or more.

During an initial consultation, a physician will record the patient’s weight and perform a thorough physical examination including:

• Checking vital signs, such as heart rate and blood pressure
  
  
• Evaluation of patient’s skin, abdomen and teeth
  
  
• Neurological examination to evaluate other potential causes of chronic vomiting, such as a brain tumor

A physician will also compile a comprehensive medical history including family history of physical and psychological disorders (e.g., depression, anxiety disorders) as well as inquire into the patient’s history of dieting and/or eating patterns. Some of the questions a physician may ask include:

• Does the patient’s weight affect their feelings of self-worth?
  
  
• Does the patient induce sickness (vomiting) because they feel uncomfortably full?
  
  
• Does the patient worry they have lost control over how much they eat?
  
  
• Does the patient ever eat in secret?
  
  
• Does the patient believe that food dominates their life?

In addition, a physician may order diagnostic tests to detect any signs of complications of bulimia including electrolyte imbalance (a loss of vitamins and minerals that are crucial for normal organ functioning, such as potassium), reduced heart rhythms (bradycardia), digestive problems (e.g., constipation) or changes in the menstrual cycle.

Additional diagnostic tests may include:

• Blood tests. Laboratory analyses – including a complete blood count (CBC) – of blood samples to measure levels of hormones, enzymes, proteins, electrolytes, vitamins and other substances to assess the function of various organ systems including the liver, kidney, thyroid and pituitary glands as well as the ovaries (female reproductive glands).
  
  
• Urinalysis. Chemical examination of a patient’s urine sample to screen for urinary tract infections, kidney disease and diseases of other organs that result in the appearance of abnormal metabolites (break-down products) in the urine.
  
  
• Electrocardiogram (EKG). This test measures the pattern of electrical impulses generated by the heart. During the procedure, electrodes (devices that detect electrical impulses) are attached to the patient’s chest. The electrical impulses are then recorded on a graph. In patients with bulimia, an EKG can help detect bradycardia and identify the presence of any damage to the heart.
  
  
• Imaging tests (e.g., x-ray, MRI). These tests are useful in detecting the presence of any damage in the chest and digestive tract or organs caused by bulimia. For example, an abdominal x-ray may reveal whether bulimia has caused a tear in the esophagus, a severe complication of prolonged bulimia that requires emergency surgery.