24-Hour Urinary Creatinine Clearance
This test measures how well your kidneys filter waste products from your blood over a full day, using a 24-hour urine sample. It helps assess kidney function and blood flow to the kidneys.
["This test helps doctors check how well your kidneys are working and identify potential kidney problems early."]
Key facts at a glance
- LOINC
- 55822-1
- Short code
- Allo-TH-DC 24h Ur-mRate
- Synonyms
- Allo-TH-DC 24h Ur-mRate
- Category
- hormone
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Your doctor may order this test if they suspect kidney disease, monitor kidney function in chronic conditions (like diabetes or high blood pressure), or evaluate kidney function before certain treatments. It’s also used to check for conditions affecting blood flow to the kidneys.
How the Test Works
You’ll collect all urine for a full 24-hour period in a special container. Blood is drawn once to measure creatinine levels in your blood. The test compares how much creatinine appears in your urine versus your blood to estimate how well your kidneys filter waste.
Sample Collection Process
You’ll need to start collecting urine immediately after your first morning urine sample is discarded. Use a clean container and refrigerate all urine samples. Bring the full 24-hour urine sample and your blood sample to the lab on the same day.
What to Expect Before the Test
No special preparation is needed, but drink plenty of fluids to help your kidneys produce urine. Avoid certain medications (like NSAIDs) that can affect kidney function unless approved by your doctor.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Low creatinine clearance may indicate kidney damage, poor blood flow to the kidneys, or other conditions like heart failure or severe dehydration. High values could suggest dehydration or overhydration. This test is critical for diagnosing and managing chronic kidney disease, kidney stones, or other kidney-related issues.
Short name
Creatinine Clearance (24h Urine)
Frequently asked questions
What does a low creatinine clearance mean?
Does diet affect this test?
How often is this test repeated?
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