Serum/plasma substance concentration for aldosterone (quantitative measurement)

Why Is This Test Done?

Your doctor may order an aldosterone test to diagnose or monitor conditions like primary aldosteroneism (Conn’s syndrome), adrenal insufficiency, or to check for hormonal imbalances affecting blood pressure or kidney function. It may also be used in conjunction with other tests to evaluate conditions like hypertension or hyperkalemia.

What to Expect Before the Test

No special preparation is usually needed, but your doctor might instruct you to avoid certain medications or dietary changes for a few days before testing. If you’re taking blood pressure medications, ask your doctor first. If you’re tested for urine aldosterone (a separate test), you may need to collect a 24-hour urine sample.

What Happens During the Test?

For a serum/plasma aldosterone test, a healthcare provider will draw blood from a vein in your arm. For a urine test, you’ll collect all urine over a 24-hour period. The sample is then sent to a lab for analysis.

What Are Possible Results?

Results are typically reported as a concentration of aldosterone in the blood or urine. Your doctor will compare these results to your individual reference ranges and clinical picture to determine if further action is needed.