A randomized controlled trial of 56 people with recurring kidney stones found that standard treatment with diet changes and medications works just as well as customized treatment based on urine testing—both approaches reduced harmful chemicals in urine equally after 8 weeks. According to research reviewed by Gram, this suggests doctors may not need expensive urine testing to help most patients prevent future kidney stones.
Researchers compared two different approaches to preventing kidney stones in people who get them repeatedly. One approach gave everyone the same medications and diet advice without testing first. The other approach tested each person’s urine first, then customized their treatment based on the results. After 8 weeks, both approaches worked equally well at reducing the chemical imbalances in urine that cause kidney stones. This suggests that doctors don’t necessarily need expensive testing to help patients prevent future stones.
Key Statistics
A 2026 randomized controlled trial of 56 adults with recurrent kidney stones found no significant difference in urinary calcium oxalate levels between those receiving standard treatment (4.7 units) and those receiving customized treatment based on urine testing (5.0 units) after 8 weeks.
In the same trial, calcium phosphate levels were nearly identical between the standard treatment group (1.3 units) and the customized treatment group (1.4 units), suggesting that urine testing did not improve short-term kidney stone prevention outcomes.
The URINE Trial showed that 54% of participants with recurrent kidney stones were women, with an average age of 44 years, and both treatment approaches successfully reduced chemical imbalances associated with stone formation without significant differences between groups.
The Quick Take
- What they studied: Whether testing urine before treating kidney stone patients works better than just giving everyone the same treatment plan
- Who participated: 56 adults (average age 44, about half women) who had experienced kidney stones multiple times before
- Key finding: After 8 weeks, both treatment approaches reduced harmful chemicals in urine equally well—the tested approach wasn’t better than the standard approach
- What it means for you: If you get kidney stones repeatedly, your doctor may not need expensive urine testing to help you prevent future stones. Standard treatment with diet changes and common medications appears to work just as well for most people.
The Research Details
This was a randomized controlled trial, which is one of the strongest types of medical research. Researchers split 56 people with recurring kidney stones into two groups. The first group (29 people) received what’s called ’empiric therapy’—they got the same diet advice and two medications (indapamide and potassium citrate) without any special urine testing. The second group (27 people) received ‘selective therapy’—their urine was tested first, and then doctors customized their treatment based on what the tests showed, potentially adding a third medication called allopurinol.
Both groups had their urine tested at the beginning, after 4 weeks, and after 8 weeks to measure chemicals that form kidney stones. The researchers specifically looked at calcium oxalate and calcium phosphate, which are the main culprits in most kidney stones.
This approach allowed researchers to directly compare whether the extra testing and customized treatment was worth the time and money compared to just treating everyone the same way.
Understanding whether testing improves outcomes is important because urine testing is expensive and time-consuming. If both approaches work equally well, doctors could save patients money and hassle by skipping the testing. However, this is a short-term study, so we don’t yet know if these results hold up over months or years.
This study was well-designed with random assignment to groups, which reduces bias. However, the sample size was small (only 56 people), and it only lasted 8 weeks. The study was conducted at a single medical center, so results might differ in other locations or populations. The short timeframe means we can’t tell if one approach stays better than the other over longer periods.
What the Results Show
The main finding was that both treatment approaches produced nearly identical results. In the group that received standard treatment without testing, the average calcium oxalate level in urine was 4.7 units. In the group that received customized treatment based on testing, it was 5.0 units—a difference so small it could easily be due to chance (p = 0.81). Similarly, calcium phosphate levels were virtually the same between groups (1.3 vs 1.4 units).
Beyond these main measurements, researchers also checked other urine characteristics that matter for kidney stone prevention. They measured urine volume, acidity level, and the amounts of calcium, oxalate, citrate, uric acid, and sodium. None of these showed meaningful differences between the two groups at 8 weeks.
This suggests that the extra effort of testing and customizing treatment didn’t provide additional benefit compared to simply giving everyone the same proven treatment plan.
The study didn’t report major side effects or complications in either group during the 8-week period. Both groups appeared to tolerate their medications well. The researchers noted that both approaches successfully reduced the chemical imbalances associated with kidney stone formation, even though one wasn’t better than the other.
Previous research has suggested that customized treatment based on urine testing might help prevent kidney stones, but this study challenges that assumption for short-term prevention. Gram Research analysis shows this trial provides important evidence that simpler, less expensive approaches may be just as effective. The findings align with a growing trend in medicine toward questioning whether more testing always leads to better outcomes.
This study has several important limitations. First, it only lasted 8 weeks, which is relatively short for evaluating kidney stone prevention—stones can take months or years to form. Second, only 56 people participated, which is a small sample size that limits how much we can generalize the findings. Third, the study was conducted at only one medical center, so results might differ elsewhere. Fourth, we don’t know if one approach might be better over longer time periods. Finally, the study only included people with calcium-based kidney stones, so results might not apply to people with other types of stones.
The Bottom Line
For people with recurring kidney stones, standard treatment with diet changes (reducing salt and animal protein, staying hydrated) combined with medications like potassium citrate appears effective without requiring expensive urine testing first. However, this recommendation is based on short-term evidence, so discuss with your doctor whether testing might still be helpful in your specific situation. Confidence level: Moderate (based on a small, short-term study).
This research matters most for people who have had kidney stones multiple times and are trying to prevent future ones. It’s also relevant for doctors deciding whether to order expensive urine testing for these patients. People with their first kidney stone or those with rare types of stones should discuss their situation individually with their doctor.
In this study, both approaches showed results within 4 weeks, with stable results by 8 weeks. However, kidney stone prevention is typically a long-term commitment. You should expect to follow diet and medication recommendations for months to see if you successfully prevent future stones.
Frequently Asked Questions
Do I need urine testing to prevent kidney stones?
A 2026 trial found that standard treatment with diet changes and medications prevented kidney stones just as effectively as customized treatment based on urine testing. However, discuss with your doctor whether testing might benefit your specific situation, especially if you have unusual stone types.
What’s the best way to prevent kidney stones from coming back?
Research shows diet changes (reducing salt and animal protein) combined with staying well-hydrated and taking prescribed medications like potassium citrate effectively prevent recurrent kidney stones. Both approaches in the trial reduced harmful urine chemicals equally within 8 weeks.
How long does it take to prevent another kidney stone?
In this 8-week trial, both treatment approaches showed results within 4 weeks. However, kidney stone prevention typically requires long-term commitment to diet and medications over months to years to truly prevent recurrence.
Are there side effects from kidney stone prevention medications?
The trial didn’t report major side effects from indapamide or potassium citrate during the 8-week period. Both groups tolerated medications well, though individual responses vary. Discuss any concerns with your doctor before starting treatment.
Can diet alone prevent kidney stones without medication?
This trial combined diet changes with medications for both groups, so it doesn’t directly answer whether diet alone works. However, both approaches included dietary modifications, suggesting diet is an important part of prevention alongside medication.
Want to Apply This Research?
- Track daily water intake (aim for 2-3 liters) and note any dietary changes like reduced salt and animal protein. Monitor for any kidney stone symptoms (flank pain, blood in urine) and log medication adherence daily.
- Set daily reminders to take prescribed medications consistently, log water intake at meals, and track dietary choices that affect stone formation (reducing processed foods high in sodium and limiting red meat).
- Create a monthly symptom check-in to note any pain or urinary changes, track medication refills to ensure consistency, and set quarterly reminders to discuss prevention progress with your healthcare provider.
This research summary is for educational purposes only and should not replace professional medical advice. The study was small and short-term; individual results may vary. If you have a history of kidney stones or are experiencing symptoms like flank pain or blood in urine, consult your healthcare provider before starting any prevention strategy. This information does not constitute medical diagnosis or treatment recommendations.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.