Quick Facts
- Sample: 24-hour urine collection
- Fasting: No fasting required
- Turn-around: 2–3 business days. May take longer based on weather, holiday, or lab delays.
Benefits
- Detect kidney stone risk early — identify hypercalciuria before stones form
- Monitor bone health — track calcium balance in metabolic bone disorders
- Convenient at-home collection — no clinic visits or doctor referrals needed
- Fast, confidential results — receive resultsin 2–3 days
- Empower treatment decisions — measure supplement or medication effectiveness
- Proactive health management — take control of calcium metabolism naturally
Who Is This Test For?
- Individuals with a history of kidney stones or at high risk
- People with bone disorders like osteoporosis or metabolic bone disease
- Those monitoring calcium or vitamin D supplementation effects
- Patients with hyperparathyroidism or suspected calcium metabolism issues
- Anyone experiencing symptoms of abnormal calcium excretion
- Individuals seeking proactive health screening without doctor referrals
How It Works – Just 3 Steps
- Order online — Select your test and complete your purchase through our secure platform
- Visit a lab — Get your blood drawn at a convenient local collection site near you
- Receive results — Access your confidential results within 2-3 business days in your online account.
FAQ
What does this test measure? This test quantifies the total amount of calcium excreted in your urine over 24 hours, helping evaluate kidney stone risk and calcium metabolism.
How accurate is 24-hour urine calcium testing? Spectrophotometry analysis provides over 90% sensitivity for detecting hypercalciuria, making it highly reliable for diagnosis (CDC 2023).
Can diet affect my results? Yes, dietary calcium intake influences urine calcium levels; follow any dietary instructions provided before testing for accurate interpretation.
What do abnormal results mean? High values suggest hypercalciuria, increasing kidney stone risk; low values may indicate malabsorption or other metabolic issues requiring follow-up.
Do I need to refrigerate my sample? Yes, keep the collection container refrigerated or on ice throughout the 24-hour period to preserve sample integrity.
How soon will I get my results? Most results are available within 1–3 business days after the lab receives your sample.
More Details
What is the purpose of this test?
The Calcium Urine Test, 24-Hour measures total calcium excreted over a full day to evaluate calcium metabolism and kidney function. This quantitative test helps detect hypercalciuria—a major risk factor for kidney stones—affecting 10–15% of adults during their lifetime. By assessing how much calcium your body eliminates, this test provides critical insights into bone health, parathyroid function, and metabolic balance. Early detection through 24-hour urine testing can reduce recurrent kidney stone incidence by up to 30% (Mayo Clinic 2024).
Who would benefit from this test?
This test is valuable for anyone concerned about calcium metabolism or kidney stone prevention. You may benefit if you have a personal or family history of kidney stones, diagnosed bone disorders like osteoporosis, or suspected parathyroid issues. People taking calcium or vitamin D supplements should monitor urinary calcium to ensure proper absorption and excretion. Those with chronic digestive conditions affecting nutrient absorption can use this test to detect calcium imbalances. Additionally, individuals experiencing symptoms like frequent urination, bone pain, muscle weakness, or unexplained fatigue may find answers through this comprehensive calcium assessment.
When should I order a Calcium Urine Test, 24-Hour?
Order this test when evaluating causes of kidney stones or assessing your risk for future stone formation. It's appropriate for monitoring calcium excretion during treatment for bone disorders or hyperparathyroidism. If you're taking calcium or vitamin D supplements, periodic testing ensures optimal dosing without excess excretion. Consider testing if you experience symptoms like increased thirst, frequent urination, bone pain, muscle cramps, or digestive upset. Order before starting or after adjusting calcium-affecting medications like thiazide diuretics. This test is also useful for dietary changes to verify their impact on calcium balance.
How do I interpret the results?
Your results show total calcium excreted over 24 hours, expressed in milligrams (mg/24 h). Interpretation depends on sex and dietary calcium intake:
Males: 55–300 mg/24 h; Females: 35–250 mg/24 h
- Meaning: Normal calcium excretion on unrestricted diet
- Action: No immediate action; maintain balanced diet and hydration
Above normal range
- Meaning: Hypercalciuria—increased kidney stone risk
- Action: Consult provider; may need dietary changes, medication, or further testing
Below normal range
- Meaning: Possible malabsorption or hypocalciuria
- Action: Evaluate calcium intake, vitamin D status, and digestive health
Values above 250 mg/24 h (men) or 200 mg/24 h (women) suggest hypercalciuria, warranting medical evaluation.
Pre-test preparation
No fasting is required for this test. Follow any dietary instructions from your healthcare provider—you may be asked to maintain your normal diet or follow a specified calcium intake (typically 600–800 mg/day) to standardize results. Avoid starting new calcium or vitamin D supplements immediately before testing unless directed. Consult your provider about temporarily holding medications that affect calcium excretion, such as thiazide diuretics or antacids. Stay well-hydrated throughout the collection period. Obtain the collection container and written instructions from the lab before beginning your 24-hour collection to ensure proper technique and accurate results.
How often should I get tested?
- Active kidney stone formers: Every 3–6 months during treatment
- Monitoring calcium/vitamin D therapy: Every 6–12 months or after dose changes
- Metabolic bone disease management: Every 6–12 months
- Hyperparathyroidism monitoring: Every 6–12 months or as directed
- Post-treatment follow-up: 3–6 months after intervention
- Preventive screening (high risk): Annually or as recommended
Why early detection matters
Early identification of abnormal calcium excretion prevents serious complications and reduces healthcare costs. Detecting hypercalciuria before kidney stones form allows you to implement dietary changes, increase hydration, or start preventive medications—reducing stone recurrence by up to 30% (Mayo Clinic 2024). Kidney stone treatment can be painful and expensive, involving emergency visits, imaging, and potentially invasive procedures. Longitudinal studies show maintaining urinary calcium below risk thresholds decreases fracture risk in patients with bone disease (Academic Journal 2024). Proactive testing empowers you to optimize calcium balance, protecting both kidney and bone health while avoiding costly interventions.
Related tests you may consider
Parathyroid Hormone (PTH) Test — differentiates causes of altered calcium metabolism and parathyroid function
Calcium Serum Test — measures blood calcium levels to complement urinary findings
Vitamin D, 25-Hydroxy Test — assesses vitamin D status affecting calcium absorption and excretion
