24-Hour Urinary Sodium and Chloride Concentration Profile
This test measures how much sodium and chloride (key minerals) are excreted in your urine over a full day. It helps assess kidney function and balance of fluids and electrolytes in your body.
["Understanding your daily mineral loss can help prevent fluid imbalances or kidney issues."]
Key facts at a glance
- LOINC
- 23920-2
- Short code
- OF .65% NaCl 24h Inc NFr RBC
- Synonyms
- OF .65% NaCl 24h Inc NFr RBC
- Category
- electrolyte
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 4.2
- Ref high
- 5.9
- Critical range
- 2 N/A – 7 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85041
- SNOMED
- 900000000000003001
- 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
Why This Test Is Done
Your doctor may order this test if they suspect conditions like kidney disease, high blood pressure, or fluid retention. It can also help evaluate how well your kidneys are filtering waste and maintaining proper mineral levels in your body.
What to Expect Before the Test
You’ll collect all urine for 24 hours, starting after you wake up and ending just before you wake up the next morning. Keep the container clean and refrigerate the sample if needed. Drink normal fluids unless instructed otherwise.
How the Test Works
Your urine is tested for sodium and chloride levels. These minerals help regulate blood pressure and fluid balance. The test measures how much is excreted daily, which can indicate kidney function or electrolyte disorders.
What the Results Mean
High levels may suggest kidney problems, excessive sweating, or certain medications. Low levels could indicate dehydration, kidney issues, or conditions like low blood pressure (hypotension). Your doctor will interpret results in the context of your health.
Reference range
Adult males: 4.2-5.9; Females: 3.8-5.1 x 10^12/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: This test is critical for diagnosing and monitoring conditions like hypertension, kidney disease, or electrolyte imbalances. It helps doctors track how well your kidneys are managing fluid and mineral balance over time.
Short name
24-Hour Urine Electrolytes
Frequently asked questions
Why do I need to collect urine for 24 hours?
What if I miss a urine sample during the 24-hour period?
Can I drink water or take medications during the test?
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 17, 2026. · Read our editorial policy