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Creatinine, Urine

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

This test measures the amount of creatinine in urine. Creatinine may be measured alone or used to account for urine concentration when evaluating other substances.

Quick summary

["Urine creatinine helps show how concentrated a urine sample is and may be used to calculate other urine test results."]

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

Key facts at a glance

LOINC
58897-0
Short code
MEK/Creat Ur
Synonyms
MEK/Creat Ur
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 the amount of creatinine in a urine sample and is often used to assess how concentrated the urine is.

Why might I need this test?

Urine creatinine may be ordered by itself, as part of a 24-hour urine collection, or alongside another urine test. When combined with substances such as urine albumin or protein, it can help interpret the result because urine concentration can vary from day to day.

How is the test performed?

A urine sample is analyzed in the laboratory to determine its creatinine concentration. If a timed collection is requested, all urine produced during the specified period must be collected in the provided container.

How do I prepare for the test?

No fasting is usually required. Follow the collection instructions provided by your healthcare professional, including whether a first-morning, random, or 24-hour urine sample is needed.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

A higher urine creatinine concentration generally means the urine is more concentrated, while a lower concentration may result from dilute urine, low muscle mass, or reduced kidney function. Urine creatinine is often most useful as part of a ratio with another urine analyte, so an isolated result should be interpreted with the rest of the laboratory report.

Short name

Urine creatinine

Frequently asked questions

Does this test diagnose kidney disease?
Not by itself. Urine creatinine is commonly used with other kidney tests, such as urine albumin, and is also affected by muscle mass and urine concentration.
Why is a urine creatinine result sometimes divided by another value?
Dividing by urine creatinine can help correct for differences in urine concentration, allowing another measurement to be compared more reliably.
Do I need to fast for this test?
Usually not. Follow your clinician's instructions about the type and timing of urine collection, especially if a 24-hour sample has been requested.
  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