Sodium Urine Concentration (24-Hour Collection)
This test measures how much sodium your body excretes in urine over 24 hours. Sodium is a mineral that helps balance fluids and blood pressure.
["Assesses kidney function and sodium balance in your body."]
Key facts at a glance
- LOINC
- 55179-6
- Short code
- Na Urate Cry Spec Ql Micro
- Synonyms
- Na Urate Cry Spec Ql Micro
- Category
- electrolyte
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 3.5
- Ref high
- 7.2
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- microscopy-light
- 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, fluid imbalances, or certain hormonal disorders that affect sodium levels. It’s also used to monitor long-term kidney health or evaluate responses to treatments for high blood pressure or heart conditions.
What to Expect Before the Test
You’ll need to collect all urine for 24 hours, typically starting after midnight one day and ending the same time the next day. Drink normal amounts of water unless instructed otherwise. Avoid special diets or medications that could affect sodium levels unless approved by your doctor.
How the Test Works
The collected urine is sent to a lab, where sodium levels are measured using a specialized method to determine your total sodium excretion over the period.
What the Results Mean
Results help identify whether your kidneys are removing sodium efficiently or if there’s an imbalance that may require medical attention. Abnormal results might indicate conditions like kidney failure, excessive sweating, or certain hormonal issues.
Reference range
NCBI: Uric Acid Male 3.5-7.2 mg/dL; Female 2.5-6.8 mg/dLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
24-Hour Sodium Urine
Frequently asked questions
How much sodium is excreted in urine over 24 hours can reveal kidney function, fluid balance, and potential underlying health issues like hypertension or metabolic disorders.
Will I need to change my diet before this test? You may need to follow a standard diet unless your doctor specifies otherwise. Avoid special sodium-restricted diets unless instructed by your healthcare provider.
What happens if my results are abnormal? If your results are outside the normal range, your doctor may recommend additional tests or treatments to address potential issues, such as adjusting medications or investigating underlying conditions.
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