24-Hour Urinary Calcium (Substance Concentration)
This test measures the total amount of calcium excreted in your urine over a 24-hour period. It helps assess kidney function and calcium balance in your body.
["Helps diagnose kidney issues or calcium-related disorders by tracking long-term urine calcium levels."]
Key facts at a glance
- LOINC
- 25876-4
- Short code
- Citrate 24h Ur-sCnc
- Synonyms
- Citrate 24h Ur-sCnc
- Category
- chemistry
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Ref low
- 20
- Ref high
- 400
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82670
- 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
Why This Test Matters
Your kidneys normally filter calcium from your blood and release it into your urine. If your body retains too much calcium (hypercalcemia) or if your kidneys can’t filter it properly, this test can reveal imbalances that may indicate conditions like kidney stones, kidney disease, or other metabolic disorders.
When You Might Need It
Your doctor may order this test if you have symptoms like frequent kidney stones, unexplained bone pain, high blood calcium levels, or if you’re at risk for kidney disease. It’s also used to monitor certain kidney-related conditions or metabolic disorders.
What to Expect Before the Test
You’ll need to collect all urine for 24 hours, starting right after you wake up and ending just before you wake up the next morning. Store the urine in a refrigerator or cool container, and keep a record of all fluids you drink. Your doctor or lab technician will provide detailed instructions.
What Happens During the Test
No special preparation is needed beyond collecting your urine sample. The lab will analyze the total calcium content in your urine over the full 24-hour period.
Reference range
Premenopausal: 20-400 pg/mL; Postmenopausal: <30 pg/mLN/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.
◆Associated findings1
Short name
24h Urine Calcium
Frequently asked questions
What causes abnormal urinary calcium levels?
How often should I get this test?
Can I drink water during the 24-hour urine collection?
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