Serum or Plasma Creatinine Concentration (Mass Concentration)
This test measures the amount of creatinine, a waste product from muscle metabolism, in your blood. It helps assess how well your kidneys are filtering blood.
["A creatinine test helps check kidney function by measuring how well your kidneys remove waste from your blood."]
Key facts at a glance
- LOINC
- 7368-4
- Short code
- Red top grass BasoBnd Ab Qn
- Synonyms
- Red top grass BasoBnd Ab Qn
- Category
- chemistry
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- lhr
- 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
Why This Test Matters
Creatinine is a byproduct of muscle breakdown and is naturally filtered out by your kidneys. High levels may indicate poor kidney function, while low levels could suggest overhydration or muscle loss. This test is often used alongside other kidney function tests to diagnose or monitor conditions like chronic kidney disease.
How the Test Works
A small blood sample is taken from your arm and sent to a lab. The lab uses a specialized method (such as enzymatic or nephelometric techniques) to measure the creatinine concentration in your serum or plasma.
What to Expect Before the Test
You can eat and drink normally before the test. Avoid excessive protein intake 24 hours before if your doctor advises it, as it may affect results. If you have diabetes or are on certain medications, discuss this with your healthcare provider to ensure accurate results.
What to Expect During the Test
The test involves a quick, painless blood draw from your vein. You may feel a slight pinch, but it usually takes only a few minutes. You can resume your usual activities immediately afterward.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Creatinine Level
Frequently asked questions
High creatinine levels may signal kidney problems, including chronic kidney disease, acute kidney injury, or conditions that reduce blood flow to the kidneys. Low levels might suggest dehydration, muscle wasting, or errors in lab processing. Regular monitoring of creatinine levels is essential for managing kidney health and other related conditions.
How often should I get this test?
Can diet or medications affect my creatinine test 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