Serum Creatinine (Creatinine Level)
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.
Kidney function is evaluated by checking creatinine levels in your blood.
Key facts at a glance
- LOINC
- 97128-3
- Short code
- HOW-HELPFUL-HAVE-ARTS-ANDRAFTS-PROJECTS-BEEN-AS-AOPING-STRATEGY-DURING-THE
- Synonyms
- —
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- 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
What Is Creatinine?
Creatinine is a byproduct of muscle breakdown that your kidneys normally filter out of your blood. High levels can indicate poor kidney function, while lower levels may suggest dehydration or other conditions affecting muscle metabolism.
Why Is This Test Done?
Doctors order creatinine tests to monitor kidney health, especially if you have symptoms like fatigue, swelling, or changes in urine output. It’s also used before surgeries, during pregnancy, or when managing conditions like diabetes or heart disease.
What Does the Result Mean?
Results are compared to a baseline or reference range provided by your healthcare provider. Abnormally high levels may signal kidney issues, while very low levels could raise concerns about muscle problems or dehydration.
How Is the Test Performed?
A blood sample is taken from a vein in your arm. The test is quick and usually done during a regular doctor’s visit or lab visit. No special preparation is needed, but fasting may be advised in some cases.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Creatinine levels are a critical marker for kidney function, as they reflect how effectively your kidneys remove waste. Chronic kidney disease (CKD) often presents with elevated creatinine, while acute kidney injury may show sudden spikes. Doctors may also use creatinine alongside other tests (like blood urea nitrogen) to assess kidney health comprehensively.
Short name
Creatinine
Frequently asked questions
How long does it take to get my creatinine test results?
Can I eat or drink before this test?
What if my creatinine level is out of the usual range?
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