Serum Creatinine (Creatinine)
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 waste in your blood."]
Key facts at a glance
- LOINC
- 60643-4
- Short code
- Na-Me Skull XR
- Synonyms
- Na-Me Skull XR
- 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-measured
- 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
Your kidneys normally filter waste products, including creatinine, from your blood. High levels of creatinine can indicate poor kidney function or damage, while low levels may suggest overhydration or other conditions. This test is often used alongside other kidney function tests to diagnose or monitor kidney disease, dehydration, or other health issues.
What to Expect Before the Test
No special preparation is needed for this blood test. You may have a small needle inserted into your arm to draw a blood sample. If you’re on a low-protein diet or have had recent muscle injury, your doctor may advise adjustments to avoid misleading results.
Common Causes of Abnormal Results
High creatinine levels may be due to kidney problems, dehydration, severe muscle breakdown, or conditions like heart failure or liver disease. Low levels might result from overhydration, certain medications, or conditions affecting fluid balance. Your doctor will review your results in the context of your overall health.
What the Results Mean
Your doctor will compare your creatinine level to standard ranges and consider your age, sex, and overall health. While reference ranges vary by lab, abnormal results prompt further evaluation, such as additional kidney tests or imaging, to identify underlying causes.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Creatinine
Frequently asked questions
How long does it take to get my creatinine test results?
Can diet affect my creatinine test results?
What if my creatinine level is higher than expected?
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