Diagnosis

If your doctor suspects that you have anorexia nervosa, he or she will typically do several tests and exams to help pinpoint a diagnosis, rule out medical causes for the weight loss, and check for any related complications.

These exams and tests generally include:

• Physical exam. This may include measuring your height and weight; checking your vital signs, such as heart rate, blood pressure and temperature; checking your skin and nails for problems; listening to your heart and lungs; and examining your abdomen.
• Lab tests. These may include a complete blood count (CBC) and more-specialized blood tests to check electrolytes and protein as well as functioning of your liver, kidney and thyroid. A urinalysis also may be done.
• Psychological evaluation. A doctor or mental health professional will likely ask about your thoughts, feelings and eating habits. You may also be asked to complete psychological self-assessment questionnaires.
• Other studies. X-rays may be taken to check your bone density, check for stress fractures or broken bones, or check for pneumonia or heart problems. Electrocardiograms may be done to look for heart irregularities.

Your mental health professional also may use the diagnostic criteria for anorexia in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published by the American Psychiatric Association.