Complete Blood Count (CBC): A Patient Guide to This Common Blood Test
This test measures the level of angiotensin II, a hormone that helps regulate blood pressure and fluid balance, in your blood.
{"Measures angiotensin II hormone in blood plasma","Helps diagnose causes of high blood pressure","Requires blood sample taken after standing upright","Used to evaluate kidney and adrenal gland function","Results help doctors understand hormone-related conditions"}
Key facts at a glance
- LOINC
- 51836-5
- Short code
- ANGIIUP
- Synonyms
- Angiotensin II upr Plas-mCnc
- Category
- chemistry
- Sample
- plasma
- Container
- Pre-chilled lavender-top (EDTA) tube with aprotinin (protease inhibitor) added to prevent angiotensin II degradation
- Units
- N/A
- Ref low
- 5
- Ref high
- 35
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–99 years
- Method
- Radioimmunoassay (RIA) or Enzyme Immunoassay (EIA)
- CPT
- 82164
- SNOMED
- 43408008
- Specimen volume
- 3-5 mL of whole blood collected in chilled EDTA tube
- Stability
- Plasma should be separated immediately in refrigerated centrifuge and frozen at -20°C or lower. Angiotensin II is highly unstable; process within 30 minutes of collection. Stable for up to 1 month at -20°C; up to 6 months at -70°C.
- Hemolysis max
- 100
- Lipemia max
- 50
- Icterus max
- 20
- TAT
- 72–168 hours
- Order
- routine
A complete blood count, or CBC, is a routine blood test that measures the different cells in your blood, including red blood cells, white blood cells, and platelets, giving your doctor a broad picture of your overall health.
The plasma angiotensin II test measures the amount of angiotensin II in your blood. Angiotensin II is a hormone produced by your body as part of the renin-angiotensin-aldosterone system (RAAS), which plays a key role in controlling blood pressure and fluid balance. This test is specifically performed with a blood sample taken after you have been in an upright position (standing or sitting).
Your doctor may order this test as part of a routine checkup, to look into symptoms such as fatigue, weakness, fever, or unusual bruising, or to monitor a condition you already have, such as anemia, an infection, or a blood disorder.
Your doctor may order this test if you have high blood pressure (hypertension) that is difficult to control, or if they suspect a problem with your kidneys or adrenal glands. The test helps determine if your body is producing too much or too little angiotensin II, which can contribute to certain medical conditions.
The test is done with a simple blood draw. A healthcare professional will clean an area on your arm, wrap a band around your upper arm, insert a small needle into a vein, and collect a small sample of blood into a tube. The procedure usually takes only a few minutes.
A healthcare professional will draw a blood sample from a vein in your arm. For accurate results, you will need to stand or sit upright for a period before the blood draw, as instructed by your doctor. The sample is then sent to a laboratory for analysis.
Results within the normal ranges usually suggest your blood cells are at healthy levels. Abnormal values may point to conditions such as anemia, infection, inflammation, or clotting problems, but your doctor will interpret your results together with your symptoms and medical history.
Abnormal angiotensin II levels can indicate various conditions. High levels may suggest conditions such as renovascular hypertension, certain adrenal gland tumors, or heart failure. Low levels may be associated with certain kidney diseases or diabetes. Your doctor will interpret your results along with other tests and your overall health condition.
Reference range
Reference values for upright plasma angiotensin II vary by laboratory and assay methodology; upright posture typically yields higher values than supine measurements due to physiologic activation of the renin-angiotensin system.N/A
No special preparation required. Patient should be on a normal sodium diet prior to specimen collection. Avoid excessive salt restriction or loading. Certain medications (ACE inhibitors, ARBs, beta-blockers, diuretics, NSAIDs) may affect results and should be noted.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
The angiotensin II test is valuable in diagnosing and evaluating hypertension (high blood pressure), particularly when it is resistant to standard treatments. It helps identify renal artery stenosis (narrowing of kidney arteries), adrenal gland disorders like Conn's syndrome or pheochromocytoma, and conditions affecting the renin-angiotensin-aldosterone system. The test is also used to monitor certain conditions and evaluate the effectiveness of treatments that target the RAAS pathway.
Frequently asked questions
Do I need to fast before this test?
Why does the test require upright positioning?
Are there any risks with this test?
How long does it take to get results?
Sources
- 1
- 2
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 15, 2026. · Read our editorial policy