"How do I know it's Addison's disease?"

Laboratory investigations can be used to detect whether the cortisol hormone levels are low in the blood and thereafter to determine the cause of the same.

The common tests that are done include:

Blood tests: To measure serum Sodium, Potassium, Cortisol and ACTH levels

ACTH Stimulation test – This test measures the rise in serum Cortisol levels after an injection of ACTH. ACTH is a hormone produced by the pituitary gland and it stimulates the adrenal gland to produce its hormones.

X-ray of abdomen – To detect calcium deposits in the adrenals

CT scan of abdomen – This can be used to detect abnormalities of the adrenal glands.

CT scan or MRI of Pituitary – This may be required if the patient has been diagnosed with Secondary Addison's disease.