24-Hour Urine Creatinine Excretion
A 24-hour urine creatinine test measures how much creatinine your body excreates in one day. It can help assess kidney function and verify that a urine collection was complete.
["This test measures daily creatinine excretion and can help evaluate kidney function and the reliability of a 24-hour urine collection."]
Key facts at a glance
- LOINC
- 44377-0
- Short code
- Hcys/Creat 24h Ur-sRto
- Synonyms
- Hcys/Creat 24h Ur-sRto
- Category
- kidney
- 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
What is this test?
Creatinine is a waste product formed as your muscles break down creatine. This test measures the amount of creatinine excreted in all urine collected over a 24-hour period, sometimes with a serum creatinine measured for comparison.
Why might I need this test?
Clinicians may use this test to evaluate kidney function, estimate daily creatinine excretion, or determine whether other measurements from a 24-hour urine collection are reliable. It may also be used when a single urine specimen cannot provide the needed information.
How is the test performed?
You usually collect all urine for exactly 24 hours, beginning and ending at the times specified by the laboratory. The urine volume is recorded, and a sample is sent for creatinine measurement. The laboratory may calculate the total amount excreted per day and compare it with blood creatinine levels.
How do I prepare for the test?
Follow the laboratory's collection instructions and record when the collection starts and ends. Stay normally hydrated, avoid unusually strenuous exercise before collection, and keep the urine refrigerated if instructed. Ask your healthcare professional before changing medicines or fluid intake.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Creatinine excretion varies with muscle mass, diet, activity, hydration, and overall health. Reduced excretion may occur with impaired kidney function but can also result from an incomplete collection, while high values may reflect increased muscle mass, intense exercise, injury, or other conditions. Results should be interpreted by your clinician using the blood creatinine, urine volume, collection quality, and your medical history.
Short name
24-hour urine creatinine
Frequently asked questions
Why is urine collected for 24 hours instead of once?
Does this test diagnose a specific kidney disease?
What if I miss part of 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