Skip to content

Creatinine, Urine

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

Measures the amount of creatinine in urine. Results may be used alone or with urine protein or albumin to help evaluate kidney function.

Quick summary

["Urine creatinine is commonly used to assess creatinine excretion and calculate urine protein or albumin-to-creatinine ratios."]

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

Key facts at a glance

LOINC
79622-7
Short code
R-B-AIB/Creat Ur-sRto
Synonyms
R-B-AIB/Creat 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 the amount of creatinine in a urine sample.

Why might I need this test?

A urine creatinine measurement can help evaluate kidney function and is often paired with urine albumin or protein. Comparing these measurements reduces the effect of differences in urine concentration.

How is the test performed?

A urine specimen is collected and tested in the laboratory to determine its creatinine concentration or total amount. Your care team may also calculate an albumin-to-creatinine or protein-to-creatinine ratio.

How do I prepare for the test?

Follow the collection instructions provided by your care team, including whether a random or timed urine sample is required. Fasting is usually unnecessary, but unusual changes in activity, muscle mass, hydration, or meat intake can affect the result.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Urine creatinine results are interpreted according to age, muscle mass, hydration, activity, and the type of urine collection. When used with urine albumin or protein, the ratio can help identify increased urinary protein loss, which may be associated with kidney disease, diabetes, or high blood pressure.

Short name

Urine creatinine

Frequently asked questions

Is fasting required for a urine creatinine test?
Fasting is usually not required. Follow your care team's instructions because a specific collection time or a complete timed collection may be requested.
Why is urine creatinine measured with urine albumin or protein?
Urine concentration can vary from sample to sample. A creatinine value helps normalize the albumin or protein measurement so small changes in urine concentration do not distort the interpretation.
What can affect urine creatinine levels?
Muscle mass, exercise, hydration, recent meat intake, pregnancy, and certain medications or illnesses can affect the amount of creatinine excreted. Your clinician will interpret the result in your overall clinical context.
  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