Aldosterone Recumbent

This test measures aldosterone, a hormone made by your adrenal glands that helps control salt and water balance. Aldosterone signals your kidneys to retain sodium and excrete potassium, which affects blood volume and blood pressure.

Recumbent means the sample is collected after you have been lying down quietly. Posture changes aldosterone levels, so measuring it while you are recumbent helps standardize the conditions. The test is usually done on a blood sample and is often interpreted together with a renin test to understand how the hormone system that regulates blood pressure is functioning.

Your clinician may order this test if you have high blood pressure that is hard to control, low potassium, or symptoms that suggest an imbalance in salt and water regulation. It helps evaluate conditions such as primary aldosteronism, where too much aldosterone is produced, and can also contribute to the assessment of adrenal insufficiency when aldosterone may be inappropriately low.

Results guide further workup and treatment choices. Knowing your aldosterone level under recumbent conditions can improve accuracy when comparing with renin and when deciding whether additional confirmatory testing, medication adjustments, or imaging is needed.

Your aldosterone level is interpreted in the context of your symptoms, blood pressure, potassium level, renin level, and medications. A higher-than-expected aldosterone can point to overproduction, while a lower-than-expected level can occur with adrenal underactivity or certain medicines. Because posture, salt intake, and timing can influence the result, standardized collection and careful review are important.

If your result is outside the expected range, your clinician may repeat testing under controlled conditions, review medicines that could interfere, or order follow-up tests such as a renin level, suppression or stimulation tests, or imaging. Do not start or stop medicines on your own; changes should be guided by your care team.