Cortisol level

Alternative names:

hydrocortisone test

What the risks are:

• excessive bleeding
• fainting or feeling lightheaded
• hematoma (blood accumulating under the skin)
• infection (a slight risk any time the skin is broken)
• multiple punctures to locate veins

Special considerations:

Physical and emotional stress can increase serum cortisol, because a normal response to stress involves increased secretion of ACTH by the pituitary gland.

Cortisol (or other glucocorticoids) in pharmacological doses (when given as a medication) reduces inflammation and inhibits the immune response. Even at physiological (normal body) concentrations, cortisol probably has an effect on the immune system and the inflammatory response, especially in people subject to chronic stress.

Cortisol is a steroid hormone released from the adrenal cortex in response to ACTH. Normally, cortisol levels rise and fall during the day (that is, diurnal variation); highest levels are at about 6 to 8 A.M. and lowest levels are at about midnight.

Cortisol levels may increase after meals. Cortisol helps to increase the release of amino acids from skeletal muscle, and fatty acids from adipose tissue. The amino acids are taken up by the liver and converted to glucose, which is subsequently secreted into the blood to be used for energy by certain tissues such as brain cells and red blood cells. The fatty acids released from the adipose tissue are used for energy by skeletal muscle, thus sparing the available glucose for use by the brain.