Nitric Oxide in Blood (Stable Isotope Dilution Mass Spectrometry)
This test measures the levels of nitric oxide, a naturally occurring chemical in your blood that helps regulate blood pressure and blood vessel function.
["Nitric oxide helps keep your blood vessels relaxed and healthy; low levels may indicate vascular issues or other health concerns."]
Key facts at a glance
- LOINC
- 771-6
- Short code
- nRBC # Bld Auto
- Synonyms
- nRBC # Bld Auto
- Category
- chemistry
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 4.2
- Ref high
- 5.9
- Critical range
- 2 N/A – 7 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- automated-count
- CPT
- 85041
- SNOMED
- 900000000000003001
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What Nitric Oxide Does in Your Body
Nitric oxide plays a key role in maintaining healthy blood flow by relaxing the walls of your blood vessels. It helps prevent blood clots and supports proper circulation. Your doctor may order this test if they suspect conditions like high blood pressure, poor circulation, or vascular diseases.
When This Test Might Be Ordered
A nitric oxide blood test may be recommended if you have symptoms like frequent headaches, fatigue, or unexplained dizziness. It could also be part of an evaluation for conditions such as Raynaud’s phenomenon, peripheral artery disease, or other vascular disorders.
How the Test Works
Blood is drawn from a vein in your arm. The sample is processed to measure nitric oxide levels using advanced mass spectrometry techniques, which detect very small amounts of this chemical in your blood.
What to Expect Before the Test
No special preparation is needed, but avoid strenuous exercise or eating a heavy meal 24 hours before the test. If you’re on blood pressure medications, check with your doctor first to ensure they don’t affect the results.
Reference range
Adult males: 4.2-5.9; Females: 3.8-5.1 x 10^12/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Nitric Oxide (NO) Blood
Frequently asked questions
Why might my nitric oxide levels be checked?
What do my results mean?
Can I affect my nitric oxide levels?
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 17, 2026. · Read our editorial policy