Serum or Plasma Aldosterone-to-Renin Ratio (ARR)
This test measures the balance between two hormones—aldosterone and renin—that help regulate your blood pressure and fluid balance.
["Helps diagnose conditions affecting your kidneys, blood pressure, or hormones."]
Key facts at a glance
- LOINC
- 10113-9
- Short code
- ST wave ED L-V2
- Synonyms
- ST wave ED L-V2
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- ekg
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Matters
Your body produces aldosterone to control how much sodium and potassium your kidneys retain, which directly impacts blood pressure. Renin is an enzyme released by your kidneys in response to low blood pressure or low sodium levels. An ARR helps doctors assess whether your kidneys are working properly or if you have conditions like primary aldosteronism (a hormone disorder) or kidney disease.
How It Works
Blood is drawn and tested for both aldosterone (a hormone) and renin (an enzyme). The ratio compares these two levels to check if your kidneys are producing them in the expected way.
Common Conditions Tested For
This test is often used to diagnose or evaluate conditions such as hypertension (high blood pressure), kidney disorders, or hormonal imbalances like aldosterone excess.
What to Expect Before the Test
No special preparation is needed, but you may be asked to avoid certain medications (like blood pressure drugs) or foods (like salt) for a short time before testing, depending on your doctor’s instructions.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Aldosterone/renin ratio
Frequently asked questions
An elevated ARR may suggest conditions like primary aldosteronism, where your body overproduces aldosterone, leading to high blood pressure and low potassium levels. A low ARR might indicate kidney problems or other hormonal imbalances that affect blood pressure regulation.
What does an abnormal ARR mean?
How long does it take to get results?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy