Cortisol or hydrocortisone, is a corticosteroid hormone synthesized in the zona fasciculata of the cortex of the adrenal glands. While the adrenal cortex also produces aldosterone (in the zona glomerulosa) and some sex hormones (in the zona reticulosa), cortisol is its main secretion.

GoldBamboo

... Why get tested?
To help diagnose Cushing syndrome or Addison disease

When to get tested?
If your doctor suspects damage to the adrenal gland

Sample required?
A blood sample drawn from a vein in the arm or a urine sample; sometimes a saliva sample may be used
...
Lab Tests Online - more...

Cortisol Systematic (IUPAC) name 11,17,21-trihydroxy-,(11beta) ...
Wikipedia - [full article]

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