Potassium/Creatinine Ratio, Urine
Measures urinary potassium relative to urinary creatinine, helping assess potassium excretion while accounting for urine concentration.
["This urine test helps evaluate how much potassium your body is excreting relative to creatinine."]
Key facts at a glance
- LOINC
- 43222-9
- Short code
- Potassium/Creat Ur-Rto
- Synonyms
- Potassium/Creat Ur-Rto
- Category
- kidney
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Ref low
- 3.5
- Ref high
- 5
- Critical range
- 2.5 N/A – 6.5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84132
- SNOMED
- 110742001
- 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?
This test measures the amount of potassium in urine compared with the amount of creatinine in the same sample. Creatinine is used as a reference marker for urine concentration, so the ratio can help show how much potassium is being excreted without being strongly affected by how dilute or concentrated the urine is.
Why might I need this test?
Your clinician may use this test to assess potassium balance, evaluate possible kidney or electrolyte problems, or monitor certain medicines that can alter potassium levels. It may also be used during the evaluation of unusually high or low blood potassium levels.
How is the test performed?
A urine sample is collected in a laboratory-provided container. Potassium and creatinine are measured, and their results are used to calculate the potassium-to-creatinine ratio. The collection time and type of urine sample should follow the instructions provided by your clinician.
How do I prepare for the test?
This test usually does not require fasting, but your clinician may specify a collection time or other preparation. Collect the urine in the correct container, avoid contaminating it with toilet paper or other material, and follow the laboratory’s storage and submission instructions.
Reference range
Adult: 3.5-5.0 mmol/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Urine potassium-to-creatinine ratio
Frequently asked questions
Does this test measure blood potassium?
Why is creatinine included in the urine test?
Do I need to collect all urine for a full day?
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