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24-Hour Urine Creatinine

Published: August 9, 2026Updated: August 16, 2026

Measures the total amount of creatinine excreted in urine collected for 24 hours to help assess kidney function and the completeness of urine collection.

Quick summary

["This test can help evaluate kidney function, but results depend on collecting all urine correctly for the full 24 hours."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
47113-6
Short code
Gold/Creat 24h Ur-sRto
Synonyms
Gold/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 produced by the muscles and filtered by the kidneys. This test measures how much creatinine is released in the urine over 24 hours.

Why might I need this test?

A clinician may order this test to assess kidney function, estimate creatinine clearance, or check whether a 24-hour urine collection was complete. It may also be used when evaluating certain medications or monitoring people with kidney disease.

How is the test performed?

You usually collect all urine into a special container for exactly 24 hours. The start and end times are recorded, and the total amount and collection time are documented before the sample is sent to the laboratory for analysis.

How do I prepare for the test?

Follow the collection instructions provided by the laboratory or clinician. Record the date and time of the first and last collection, include every urine sample, and ask the laboratory how to store the container. Do not change your diet, fluid intake, or medications unless your clinician instructs you to do so.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

24-Hour Urine Creatinine

Frequently asked questions

Do I need to fast for a 24-hour urine creatinine test?
Fasting is generally not required, but follow any specific instructions from your clinician or laboratory. Maintaining your usual diet and fluid intake usually helps produce a representative collection.
What happens if I miss part of the urine collection?
A missed sample can make the result inaccurate and may require you to repeat the collection. Contact the laboratory or clinician for guidance rather than estimating or adding a missed sample yourself.
Can medications affect the result?
Some medications can influence urine creatinine levels. Tell your clinician and laboratory about all medicines and supplements you use, but do not stop prescribed medication without instructions.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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