Urea/Creatinine Ratio, Urine
A urine test that compares urea with creatinine to help assess hydration, protein breakdown, and kidney function.
["This ratio gives your clinician context about hydration and kidney function when interpreted with other tests."]
Key facts at a glance
- LOINC
- 40487-1
- Short code
- Urea/Creat Ur-Rto
- Synonyms
- Urea/Creat Ur-Rto
- Category
- kidney
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Ref low
- 7
- Ref high
- 20
- Critical range
- — – 100 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84520
- SNOMED
- 2739004
- 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?
The urine urea/creatinine ratio measures the relative amounts of urea and creatinine in a urine sample. Urea reflects protein breakdown and hydration, while creatinine is affected by muscle mass and kidney filtering.
Why might I need this test?
A clinician may order this test as part of an evaluation of kidney function, dehydration, or fluid balance. It may also help assess how the body is breaking down protein, particularly in people with illness or symptoms affecting nutrition.
How is the test performed?
A urine sample is collected and tested in the laboratory. The laboratory measures the concentrations of urea and creatinine and calculates their ratio. The result may come from a single urine specimen or a timed collection, depending on the order.
How do I prepare for the test?
Follow the collection instructions provided by your healthcare professional, including whether a first-morning or timed sample is required. Fasting is generally not necessary, but tell the laboratory if you are pregnant or taking medicines that may affect the result.
Reference range
Adult: 7-20 mg/dLN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A lower ratio may occur with inadequate fluid intake or reduced urine production, while a higher ratio may be associated with increased protein breakdown, recent bleeding, fever, or high protein intake. Changes in kidney function can also affect the result. Your clinician will interpret it alongside symptoms, hydration status, medications, and other kidney tests.
Short name
Urine urea/creatinine ratio
Frequently asked questions
Does this test require a 24-hour urine collection?
Is fasting required for a urine urea/creatinine ratio?
Can I use this result to diagnose kidney disease?
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