Creatinine Clearance (Calculated from Urine and Blood Samples)
This test measures how well your kidneys filter waste products from your blood, using a simple urine and blood sample. It helps assess kidney function and overall kidney health.
["A creatinine clearance test helps doctors check how well your kidneys are working by measuring how quickly waste products leave your blood."]
Key facts at a glance
- LOINC
- 35913-3
- Short code
- CT Guided Abd Drain+cath place
- Synonyms
- CT Guided Abd Drain+cath place
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- ct
- 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 Does This Test Measure?
Creatinine clearance evaluates kidney function by calculating how efficiently your kidneys filter waste (creatinine) from your blood into urine. It uses a 24-hour urine collection and a blood sample to determine the rate at which waste is removed. This test is often used to diagnose and monitor kidney disease, track kidney function over time, and guide treatment decisions.
Why Is This Test Done?
Doctors may order this test if you have symptoms of kidney problems (like fatigue, swelling, or frequent urination), if you have a condition that affects kidney function (like diabetes or high blood pressure), or if you’re at risk for kidney disease. It’s also used before surgeries or procedures that may impact kidney function.
How Is This Test Performed?
You’ll collect all urine for a full 24-hour period (starting after your first morning urine and ending just before your next morning urine). A blood sample is taken at the end of this period. Lab technicians analyze the urine and blood to calculate your creatinine clearance rate.
What Should You Expect Before the Test?
No special preparation is needed for the urine collection, but you may need to adjust your fluid intake slightly to ensure accurate results. Avoid certain medications (like NSAIDs) that could affect kidney function. If you’re pregnant or have a kidney condition, let your doctor know before starting the test.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is critical for diagnosing and monitoring kidney disease, assessing how well medications are clearing from your body, and guiding treatment plans for conditions like chronic kidney disease, kidney stones, or pre-existing kidney issues. It helps doctors identify early signs of kidney dysfunction and adjust care accordingly.
Short name
Creatinine Clearance
Frequently asked questions
How long does the urine collection take?
Will I need to take any special steps during the 24-hour urine collection?
Can I drink alcohol or caffeine during the urine collection?
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