Investigations to help decide if a patient requires admission include

ECG – all patients should have an ECG. Check for:

  • Bradyarrhythmia’s
  • Long QTc
  • Non-specific T wave changes
  • Hypokalaemia

Blood tests – may be normal unless there are purging behaviours, such as laxatives or diuretics:

  • FBC
  • U&Es – may be affected by dehydration, or malnutrition
    • Low sodium suggestive of water loading
    • Low potassium suspicious of vomiting or laxative abuse
  • Glucose – hypoglycaemia maybe associated with possible occult infection
  • Calcium
  • Magnesium
  • Phosphate
  • LFTs – raised transaminases with malnutrition

Additional investigations may be required, if admission is being considered, to assess nutritional state:

  • Thyroid function tests
  • Amylase
  • Coeliac screen
  • Vitamin D
  • Iron studies, vitamin B12, folate
  • Zinc, copper selenium