Creatinine Clearance (Serum-Based, 24-Hour Urine Collection)
This test measures how well your kidneys filter waste products from your blood, using a 24-hour urine sample and a blood draw. It helps assess kidney function and overall renal health.
["A creatinine clearance test helps doctors check how well your kidneys are working by tracking how efficiently they remove waste from your blood."]
Key facts at a glance
- LOINC
- 110051-0
- Short code
- C trach C IgM Msmt Ser
- Synonyms
- C trach C IgM 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
- CPT
- 82784
- 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 Is Done
Your doctor may order this test if they suspect kidney disease, monitor chronic kidney conditions, or evaluate kidney function after certain treatments or injuries. It’s also used to guide decisions about medications that affect kidney function.
How the Test Works
To calculate creatinine clearance, your healthcare provider will collect a 24-hour urine sample (typically over 24 hours) and a blood sample. The urine sample measures creatinine levels, while the blood sample provides baseline creatinine levels. The results are then used to estimate how much blood your kidneys filter each minute.
Sample Collection Process
You’ll need to collect all urine produced in a 24-hour period, including at night, in a special container. You’ll also have a blood draw on the same day. Follow your doctor’s instructions carefully to ensure accurate results.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to avoid certain medications or supplements that could affect results. Drink plenty of water unless instructed otherwise, as hydration helps with urine collection.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Creatinine clearance is a key indicator of kidney function. Lower than expected results may signal kidney damage, reduced blood flow to the kidneys, or other underlying conditions like dehydration or heart problems. Higher-than-expected results might indicate overhydration or errors in urine collection. This test helps guide treatment plans for chronic kidney disease, kidney stones, or other conditions affecting kidney health.
Short name
Creatinine Clearance
Frequently asked questions
What does a creatinine clearance test measure?
How long does it take to get results from this test?
Can I eat or drink normally before this test?
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