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 check via creatinine levels."]
Key facts at a glance
- LOINC
- 109169-3
- Short code
- C trach G+F+K Ab Msmt Ser
- Synonyms
- C trach G+F+K Ab Msmt Ser
- 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
Why This Test Matters
Creatinine is a byproduct of muscle breakdown and is normally filtered out of your blood by your kidneys. High levels can indicate reduced kidney function, while low levels may suggest overhydration or other conditions. This test is often used alongside other measures, like blood urea nitrogen (BUN), to evaluate kidney health.
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 blood, which usually causes only minor discomfort. If you’re dehydrated or have recently eaten a large meal, your results might be affected, so it’s best to drink water and eat normally the day of testing.
What the Results Mean
Results are interpreted in relation to your overall health, age, sex, and other medical conditions. While creatinine levels alone don’t diagnose kidney disease, they’re part of a broader assessment. Your healthcare provider will discuss any changes in your results with you.
Common Causes of Abnormal Results
High creatinine levels may signal kidney problems, dehydration, or muscle disorders. Low levels might suggest overhydration, liver disease, or certain medications. Other factors, like diet (high-protein foods) or exercise, can temporarily influence results.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Creatinine is a critical marker for kidney function. Chronic kidney disease (CKD) is often detected early through repeated monitoring of creatinine and BUN levels. Abnormal results prompt further evaluation, such as additional blood tests, imaging, or urine tests, to identify underlying causes and guide treatment.
Short name
Creatinine
Frequently asked questions
How often should creatinine levels be checked?
What can affect my creatinine test results?
Can creatinine levels change over time?
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