Serum/Plasma Creatinine Concentration (Standard Method)
This test measures the amount of creatinine, a waste product from muscle breakdown, in your blood or plasma. 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
- 36747-4
- Short code
- XR Mandible Views Obl
- Synonyms
- XR Mandible Views Obl
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- xr
- 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
Creatinine levels can indicate how efficiently your kidneys filter blood. High levels may suggest kidney problems, while low levels could indicate dehydration or muscle disorders. This test is often used alongside other kidney function tests to diagnose conditions like chronic kidney disease.
What to Expect Before the Test
You may be asked to fast for 8–12 hours before the test, but this depends on your doctor’s instructions. Bring any medications you’re taking, as some may affect results. Avoid strenuous activity or excessive fluid intake on the day of testing.
How the Test Is Performed
A blood sample is drawn from a vein, usually in your arm. The sample is sent to a lab for analysis using standard methods to measure creatinine concentration.
Possible Results and Interpretation
Results are compared to reference ranges, but exact values can vary by lab. High creatinine levels may signal kidney issues, while very low levels may require further investigation for causes like dehydration or muscle atrophy.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Creatinine is a reliable marker for kidney function because it’s produced consistently by muscle metabolism and filtered by the kidneys. Elevated levels often prompt further evaluation for chronic kidney disease, acute kidney injury, or other conditions affecting kidney function. Low levels may raise concerns about dehydration, malnutrition, or muscle disorders, though they’re less common.
Short name
Creatinine
Frequently asked questions
How often should I get this test?
What can affect my creatinine levels?
Do I need to prepare differently if I’m pregnant?
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