The aldosterone blood test measures the level of the hormone aldosterone in blood.
Aldosterone can also be measured using a urine test.
A blood sample is needed.
Your health care provider may ask you to stop taking certain medicines a few days before the test so that they don't affect the test results. Be sure to tell your provider about all the medicines you take. These include:
Do not stop taking any medicine before talking to your doctor. Your provider may recommend that you eat no more than 3 grams of salt (sodium) per day for at least 2 weeks before the test.
Or, your provider will recommend that you eat your usual amount of salt and also test the amount of sodium in your urine.
At other times, the aldosterone blood test is done right before and after you receive a salt solution (saline) through the vein (IV) for 2 hours. Be aware that other factors can affect aldosterone measurements, including:
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging sensation. Afterward, there may be some throbbing or a slight bruise. This soon goes away.
This test is ordered for the following conditions:
Aldosterone is a hormone released by the adrenal glands. It helps the body regulate blood pressure. Aldosterone increases the reabsorption of sodium and water and the release of potassium in the kidneys. This action raises blood pressure.
Aldosterone blood test is often combined with other tests, such as the renin hormone test, to diagnose over- or under-production of aldosterone.
Normal levels vary:
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test results.
A higher than normal level of aldosterone may be due to
A lower than normal level of aldosterone may be due to:
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
Reviewed By: Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.