Platform
Company
Urinalysis
Review status
Currently under review
Pending specialist review and validation.
The Oxalate 24 Hour Urine test measures the total amount of oxalate you pass in your urine over a full day. Oxalate is a natural substance made by your body and found in certain foods. In urine, it can combine with calcium to form crystals that may contribute to kidney stones.
This test is usually performed as part of a metabolic evaluation for kidney stones or when your clinician suspects conditions that increase oxalate, such as certain intestinal disorders or rare inherited problems. Because it collects all urine for an entire day, it provides a more complete picture than a single urine sample and can be used to monitor how diet or treatments are working over time.
Too much oxalate in urine can raise the risk of calcium oxalate stones, the most common type of kidney stone. Knowing your daily oxalate output helps your clinician tailor prevention strategies, including dietary adjustments, optimizing calcium intake with meals, and medications that improve urine chemistry.
Your clinician may order this test if you have recurrent stones, a first stone at a young age, bowel disease, prior bariatric surgery, or unexplained kidney issues. It can also help evaluate for primary hyperoxaluria, a rare genetic condition, and track response to treatment when that diagnosis is suspected or confirmed.
Your result is interpreted alongside other urine measurements and how well the sample was collected. Higher values can reflect high dietary oxalate, low calcium intake with meals, increased production by your body, fat malabsorption, or use of high-dose vitamin C. Lower values may indicate effective dietary control or low intake.
If your level is higher than expected, your clinician may verify that the 24 hour collection was complete, review your diet and supplements, and consider repeat testing. Additional measurements such as urine calcium, citrate, pH, and total volume often help clarify why oxalate is elevated. If results suggest a genetic or intestinal cause, referral to a specialist may be recommended.
Regardless of the result, staying well hydrated, pairing calcium-containing foods with higher oxalate foods, and treating underlying gut conditions can help reduce stone risk. Avoid making major diet or supplement changes on your own; discuss a plan with your care team.
Reference intervals vary by laboratory, analyzer, methodology, population, and units. The ranges shown here are for education only. Always interpret your results against the reference interval printed on your own lab report.
Missing any urine during the 24 hour period, collecting too long or too short, or not keeping the container cool can distort results. Follow the collection instructions closely and record start and stop times.
Spinach, beets, nuts, rhubarb, chocolate, and certain teas can raise urinary oxalate. Your clinician may review your typical diet or suggest a targeted food diary before repeat testing.
Too little calcium with meals can increase oxalate absorption from the gut. Pairing appropriate calcium sources with higher oxalate foods can lower oxalate reaching the urine.
High-dose vitamin C can be converted to oxalate and raise urine levels. Discuss any supplements, powdered drinks, or fortified products you use before testing.
Inflammatory bowel disease, celiac disease, chronic pancreatitis, and some bariatric procedures can cause fat malabsorption, which increases oxalate absorption and urinary excretion.
Drugs like orlistat and topiramate can affect oxalate handling. Frequent antibiotics may reduce gut bacteria that degrade oxalate, potentially increasing urine oxalate.
Low fluid intake concentrates oxalate in urine, increasing crystal formation risk. Consistent daily fluid intake helps keep urine diluted, which supports stone prevention.
Primary hyperoxaluria and other rare disorders can cause very high oxalate output. If suspected, your clinician may order confirmatory testing and discuss specialized therapies.
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