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Creatinine, Urine — Assay Protocol

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

Measures the amount of creatinine in urine using a defined laboratory protocol. Urine creatinine is often used to evaluate urine concentration and validate other urine measurements.

Quick summary

["Urine creatinine helps show how concentrated a urine sample is and is commonly used to assess other urinary test results."]

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

Key facts at a glance

LOINC
62811-5
Short code
Urinary creatinine assay proto
Synonyms
Urinary creatinine assay proto
Category
kidney
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
0.6
Ref high
1.3
Critical range
— – 10 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
phenx
CPT
82565
SNOMED
247997009
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

What is this test?

This test measures creatinine, a waste product produced by muscle metabolism, in a urine sample. The assay protocol defines how the specimen is collected, handled, and analyzed.

Why might I need this test?

Urine creatinine may be measured to assess how concentrated the urine is. It is also used to check the completeness of timed urine collections and to interpret or calculate other urinary test results.

How is the test performed?

A urine specimen is collected as directed and analyzed in the laboratory to determine its creatinine level. If a 24-hour collection is requested, all urine produced during the specified period must be included.

How do I prepare for the test?

Follow the collection instructions provided by your healthcare professional, including any required fasting, timed collection, or refrigeration. Your clinician may advise you about temporary changes in meat intake, supplements, or exercise.

Reference range

Adult male: 0.7-1.3 mg/dL; Female: 0.6-1.1 mg/dLN/A

Specimen: serum

No special preparation required. Stay well hydrated.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Urine creatinine assay

Frequently asked questions

Is urine creatinine the same as a blood creatinine test?
No. Blood creatinine measures creatinine in the bloodstream, while urine creatinine measures it in urine. The two results may be used together to evaluate kidney function.
Why is urine creatinine included with other urine tests?
Creatinine helps indicate the concentration of the urine sample. This allows other urine measurements to be interpreted more accurately.
Do I need to collect urine for 24 hours?
That depends on the order and the assay protocol. Collect urine for the full time specified by your healthcare professional, including every sample during that period if a timed collection is required.
  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