Quick Facts
- Sample: Urine, collected over a 24-hour period
- Fasting: No fasting required, but follow a diet with about 3 grams (135 mmol) of sodium per day for at least 2 weeks (preferably 30 days) before testing. Obtain a 24-hour urine collection container from the laboratory, collect all urine for 24 hours, keep the specimen refrigerated or cool during collection, and return it promptly to the laboratory. Certain medications and substances may affect results, so consult your healthcare provider before making any changes to your medications.
- Turnaround: 10-14 days, may take longer due to weather, holidays, or lab delays
What This Test Measures
This test measures the amount of aldosterone excreted in your urine over a 24-hour timed collection. Aldosterone is a hormone released by the adrenal glands that helps your kidneys manage the balance of sodium, water, and potassium, which in turn supports healthy blood pressure and fluid balance.
The result reflects your total aldosterone output over the full collection period, not a single point-in-time value. Because the amount of sodium in your diet, kidney function, and certain medications can all affect aldosterone excretion, this test is intended to evaluate aldosterone production specifically, not other adrenal hormones or kidney function markers.
Benefits
- Measures 24-hour aldosterone excretion in urine
- Helps evaluate adrenal gland hormone production
- Supports assessment of high blood pressure causes
- Helps assess unexplained low potassium levels
- Provides a timed result reflecting daily hormone output
- Can be ordered without fasting beforehand
Who Is This Test For?
- People with a healthcare provider evaluating unexplained high blood pressure
- People being assessed for unexplained low potassium levels
- Individuals whose provider wants to evaluate adrenal aldosterone production
- People with a family or personal history of adrenal-related blood pressure issues
- Individuals being monitored for a known adrenal or aldosterone-related condition
How It Works
- Order Your Test Online
- Visit a Local Lab
- Get Results Online
FAQ
1. What is the purpose of this test?
This test measures the amount of aldosterone excreted in your urine over a 24-hour collection period, reflecting your total hormone output during that time rather than a single point-in-time reading. Aldosterone is released by the adrenal glands and helps regulate sodium, potassium, and water balance, which in turn affects blood pressure. The test is designed to evaluate aldosterone production specifically, not other adrenal hormones, electrolytes, or kidney function markers. Your healthcare provider may use this result, along with other clinical information, to help evaluate its possible role in blood pressure or electrolyte concerns.
2. Who should consider this test?
This test may be appropriate if your healthcare provider is evaluating unexplained high blood pressure, assessing unexplained low potassium levels, or investigating adrenal aldosterone production as part of an ongoing workup. It is typically ordered as part of a broader clinical evaluation rather than on its own, and it does not replace a full medical assessment.
3. Do I need to fast or prepare before this test?
No fasting is required. However, you should follow a diet containing approximately 3 grams (135 mmol) of sodium per day for at least 2 weeks, and preferably 30 days, before testing. Certain medications and substances, including diuretics, antihypertensive medications, cyclic progestational agents, estrogen, and licorice, may affect your results, so consult your healthcare provider before stopping any medications.
4. How quickly will I get results?
Results are typically available in 10-14 days. Turnaround may take longer depending on weather, holidays, or other lab delays.
5. How do I interpret the results?
The meaning of your aldosterone result depends on your individual health history, current symptoms, sodium intake, medications, and other laboratory findings. Because many prescription and nonprescription medications can affect aldosterone levels, results should always be interpreted alongside your full clinical picture. A result outside the expected range does not automatically confirm a specific condition, and a result within the expected range does not automatically rule one out.
Disclaimer: Reference ranges may vary by laboratory. Listed ranges are general guidelines and may differ from those used by the performing lab. Always consult your healthcare provider for interpretation.
6. What should I do if my results are abnormal?
Review a result outside the expected range with a qualified healthcare provider, who can determine whether additional evaluation is appropriate based on your specific circumstances.
7. How often should I get tested?
There is no fixed schedule for repeat aldosterone urine testing. Follow-up testing frequency should be determined by your healthcare provider based on your individual health needs and any ongoing evaluation.
Pre-test preparation
Before collection, take your lab order to the laboratory to obtain the appropriate 24-hour urine collection container. No fasting is required; however, you should follow a diet containing approximately 3 grams (135 mmol) of sodium per day for at least 2 weeks, and preferably 30 days, before testing. Certain medications and substances, including diuretics, antihypertensive medications, cyclic progestational agents, estrogen, and licorice, may affect your results, so consult your healthcare provider before stopping any medications. Collect all urine over a 24-hour period, refrigerate or keep the specimen cool during collection, label the container with the required information, and return it promptly to the laboratory.
Do not stop prescribed medication unless instructed by your healthcare provider.
