N-Monomethyl-L-arginine/Creatinine [Mass Ratio], Urine
Measures urinary N-monomethyl-L-arginine relative to creatinine, a marker associated with nitric oxide biology and cardiovascular risk.
["This urine test may help assess cardiovascular risk factors, but abnormal results require clinical interpretation and do not diagnose heart disease."]
Key facts at a glance
- LOINC
- 79597-1
- Short code
- N-monomethylarginine/Creat Ur-sRto
- Synonyms
- N-monomethylarginine/Creat Ur-sRto
- Category
- kidney
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What is this test?
N-monomethyl-L-arginine, or NMMA, is a compound that can affect nitric oxide, a substance that helps blood vessels relax. This test measures the amount of NMMA in urine relative to creatinine, which helps account for differences in urine concentration.
Why might I need this test?
It may be ordered as part of an evaluation of cardiovascular risk or conditions related to blood-vessel function. It is a specialized test and is not usually used by itself to diagnose a disease.
How is the test performed?
A urine sample is analyzed for NMMA and creatinine. The laboratory compares the amounts of the two substances to calculate the NMMA-to-creatinine ratio. Your clinician will explain whether a single urine sample or timed urine collection is required.
How do I prepare for the test?
Follow your clinician or laboratory's collection instructions. Fasting is generally not required, and you should not change medications or fluid intake unless specifically told to do so. If timed collection is required, record when the collection began and ended.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A higher-than-expected NMMA-to-creatinine ratio may be associated with impaired nitric oxide activity, blood-vessel dysfunction, and increased cardiovascular risk. It can also occur with kidney disease and some other health conditions, so an abnormal result does not establish a specific diagnosis. The result should be interpreted with symptoms, medical history, medications, and other cardiovascular risk factors.
Short name
Urinary NMMA-to-creatinine ratio
Frequently asked questions
What does a high NMMA-to-creatinine ratio mean?
Is this the same as an ADMA test?
Does an abnormal result mean I have heart disease?
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