I was just wondering if anyone has information on what is considered a low cortisol when a ACTH test is done?

March 9, 2010

Cortisol, which is a corticosteroid hormone, can be called the main "stress hormone" in your body. It is a steroid hormone that activates your body in times of stress. It boosts your energy, enabling you to carry out your daily activities and also makes it possible for you to meet the everyday challenges of life. Its primary role is to maintain the appropriate level of energy in your body, to deal with physical or emotional stress.

Adrenocorticotropic Hormone (ACTH), as the name suggests, is a hormone that stimulates the adrenal cortex. (The adrenal cortex produces cortisol and other hormones, such as aldosterone. It secretes corticosteroids and other hormones directly into the bloodstream). Measuring cortisol levels, through a blood test or a urine test, can help you to diagnose if you suffer from any hormonal diseases like Cushing’s disease or Addison’s disease. A test is advisable, if you have any of the following symptoms:

  • Loss of appetite
  • Weight loss
  • Muscle weakness
  • Fatigue
  • Increased skin pigmentation

All the above conditions are signs of low cortisol. Normally, the level of cortisol is the lowest in individuals at around midnight and at the highest, early in the morning. Results of a normal cortisol level, for a blood sample taken in the morning, are 6 - 23 ug/dl, whereas a sample taken in the evening will normally have the cortisol level that ranges from 3 - 15 ug/dl.

If the findings of the initial test show low cortisol, the doctor could advise you to go in for an ACTH stimulation test. The test involves measuring the concentration of cortisol in your blood, before and after an injection of synthetic ACTH. If the functioning of the adrenal cortex is fine, then your cortisol levels will rise, with this stimulation. If the glands are damaged, the response will be limited.

If you do respond to the ACTH stimulation test, then the problem is probably due to the insufficient production of ACTH, by the pituitary. However, if you do not respond to the test, then the problem is probably based in the adrenal gland and it could be a sign of Addison’s disease.

Increasing cortisol: Consumption of certain drugs can increase the levels of cortisol. For example, the diuretic spironolactone and estrogen hormone therapy could have this effect. Recent studies have also shown that drinking 2 to 3 cups of coffee per day can probably help raise cortisol levels. Low cortisol levels can be a serious condition and may need to be treated, after consulting a doctor.

Submitted by M T on March 9, 2010 at 12:18

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