Description
This test measures the amount of cortisol in a blood sample. Cortisol follows a daily rhythm, highest in the early morning and lowest late at night, so the sample must be taken at the time the instructions specify for the result to mean anything. The kit contains what is needed to collect the sample and return it to the laboratory, and the report gives the result against a reference range.
Cortisol also changes with illness, shift work, pregnancy, steroid medicines and hormonal contraception, so tell the laboratory what you take. A single measurement does not diagnose or exclude a disorder of the adrenal glands, and it does not measure stress itself. Discuss the report with a doctor, particularly if the result falls outside the reference range.
- Laboratory blood test measuring the cortisol level in one sample
- Sample timing matters, since cortisol follows a daily rhythm
- Steroid medicines and hormonal contraception affect the result
- A single result does not diagnose or exclude an adrenal disorder
