Serum Creatinine (Creatinine Level)
This test measures the level of creatinine, a waste product from muscle metabolism, in your blood. It helps assess how well your kidneys are filtering blood.
["Kidney function depends on this test to check how efficiently your kidneys remove waste from your blood."]
Key facts at a glance
- LOINC
- 15320-5
- Short code
- Volume Testis-R by AUT
- Synonyms
- Volume Testis-R by AUT
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- us-derived-aut
- 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 Is This Test Done?
Your doctor may order a creatinine test to evaluate kidney function, monitor chronic kidney disease, check for kidney-related conditions, or assess overall health before certain procedures. It’s often used alongside other tests like blood urea nitrogen (BUN) to get a fuller picture of kidney health.
What Does a High or Low Level Mean?
High creatinine levels may indicate poor kidney function, dehydration, or conditions like heart disease or muscle disorders. Low levels might suggest overhydration or liver disease, though this is less common. Your results will be compared to your overall health and other tests for accurate interpretation.
How Is This Test Performed?
A blood sample is taken from a vein, usually in your arm. The sample is sent to a lab where it’s analyzed to measure creatinine concentration. The test is quick and typically done during a regular doctor’s visit or lab visit.
What Should I Expect Before or After the Test?
No special preparation is needed for most adults, but if you’re on certain medications (like diuretics) or have a history of kidney issues, your doctor may give specific instructions. After the test, you can resume normal activities unless your doctor advises otherwise.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Creatinine levels are a key marker for kidney function because it’s directly related to how well your kidneys filter blood. Chronic kidney disease (CKD) is often detected early through elevated creatinine, as it reflects declining kidney function over time. Additionally, creatinine can help diagnose conditions like acute kidney injury (AKI) or assess the need for dialysis. While it’s not the only test for kidney health, it’s a critical part of the picture.
Short name
Creatinine
Frequently asked questions
How often should I get this test?
Can diet or exercise affect my creatinine levels?
What if my results are outside the normal 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