The study, “ Effect of Phyllanthus niruri on metabolic parameters of patients with kidney stone: a perspective for disease prevention,” by Pucci et al. (2018) evaluates Phyllanthus niruri benefits for kidney health in adults with small upper urinary tract stones. Using a prospective clinical design, the researchers followed patients given a standardized Phyllanthus niruri infusion and monitored changes in serum laboratory values, 24-hour urine metabolic parameters, and ultrasound findings.

The research focuses on metabolic risk factors linked to kidney stone formation, including urinary electrolytes and stone-forming substances, to better understand how Phyllanthus niruri may influence kidney-related metabolic processes. The authors also tracked symptoms during and after infusion use to document both observed benefits and potential adverse effects under real-world clinical follow-up.

The authors describe urolithiasis as a condition with many overlapping risk factors. These include congenital and genetic influences, environmental and dietary issues, and metabolic problems. They also point out that chronic diseases like obesity, hypertension, and diabetes are associated with urinary calculus formation. According to the scientific paper, the worldwide prevalence of urinary calculi is 8.8 percent, and the recurrence rate can reach 50 percent within 10 years after the first episode.

The authors note that low urine volume and high intake of calories, sodium, and protein, along with metabolic disturbances such as hypercalciuria and hypocitraturia, are commonly involved in stone development. They explain that modifying these risk factors through dietary guidance, lifestyle changes, and specific medications can reduce recurrence by at least 50 percent.

Alongside these conventional strategies, the paper reviews the traditional use of medicinal plants in urinary lithiasis. Phyllanthus niruri, commonly referred to as “stone breaker tea,” appears here as a plant that is inexpensive, widely available, and described as having a low incidence of adverse effects. The authors reference earlier studies that reported anti-inflammatory, anti-hyperuricemic, and diuretic properties for this plant, along with potential effects on kidney stone formation. However, they stress that clinical data in humans remain limited, which motivated their prospective trial.

The study was conducted at the Urologic Division of the Clinical Hospital, University of São Paulo, Medical School. Eligible patients were between 18 and 60 years of age and had one or more kidney stones under 10 millimeters, confirmed by ultrasonography or computed tomography. The authors excluded individuals with serum creatinine above 2.0 mg/dL, urinary tract infection, uncontrolled diabetes, chronic liver disease, cancer, or pregnancy.

The design included three stages. At baseline, patients did not use P. niruri and underwent full evaluation. During the P. niruri stage, they consumed an infusion made from a dry extract of the plant for 12 weeks, prepared according to literature recommendations. There was a one-week rest period after each week of use. After that, they entered a 12-week washout period without P. niruri. Each person was followed across all three phases, so each patient served as his or her own control over a total of 26 weeks.

Patients were seen monthly and received 60 sachets of P. niruri dry extract, each with 4.5 grams of the herb. They were instructed to use 250 milliliters of boiling water per sachet and to drink two sachets per day. The plant material came from Brazilian manufacturers, was shade dried, stored under controlled conditions, and treated with gamma irradiation to prevent fungal or bacterial contamination. The authors note that this plant is indicated for urinary tract disorders such as renal lithiasis, cramps, cystitis, and nephritis, and has been described as having analgesic, anti-inflammatory, and hepatoprotective properties.

At each stage, the team measured blood pressure and anthropometric data such as weight, height, and body mass index. Serum testing included a complete blood count, kidney and liver markers, electrolytes, lipids, and other routine measures. Twenty-four-hour urine collections were analyzed for calcium, oxalate, citrate, uric acid, magnesium, sodium, potassium, creatinine, urea, phosphorus, and pH, and a urine culture was obtained. Renal ultrasonography was performed in all three phases by radiologists who were blinded to the study period.

For the statistical analysis, the authors used analysis of variance for repeated measures, taking into account the three different time points, and then applied Tukey and McNemar tests where appropriate. The significance level was set at 5 percent.

Out of 430 initially screened individuals, 75 met the inclusion criteria, and 56 completed all stages of the study. Most of these 56 patients were women (64.3 percent) and Caucasian (92.8 percent). The mean age was 44 years, and the baseline body mass index averaged 27.2 kg/m². Many participants had comorbid conditions, including hypertension and metabolic syndrome, and nearly half were taking antihypertensive drugs.

Across baseline, P. niruri use, and washout, most serum measures did not change significantly. Values such as serum creatinine, uric acid, sodium, potassium, and calcium remained stable. One exception was alkaline phosphatase, which decreased from 67.7±22.2 to 63.5±20.6 mg/dL after the P. niruri phase, with a p value of 0.017. The authors describe this reduction as favorable and note the link between alkaline phosphatase, bone metabolism, and calculus formation in patients with hypercalciuria.

In 24-hour urine collections, the main overall change was an increase in potassium excretion. Potassium rose from 47.3±16.7 mg per 24 hours at baseline to 56.2±21.8 mg per 24 hours at washout, with a p value of 0.017. When the authors looked at electrolytes corrected for creatinine, they observed significant increases in both potassium/creatinine and magnesium/creatinine ratios between baseline and washout. In the conclusion of the paper, they summarize this by stating that “the use of the tea of this plant increases urinary excretion of magnesium and potassium.”

At the start of the study, several metabolic disturbances were common. Hypernatriuria affected 60.7 percent of patients, while hypocitraturia and hypercalciuria were each present in 42.8 percent. Low urine volume occurred in 55.3 percent of the group, hyperuricosuria in 10.7 percent, and hyperoxaluria in 8.9 percent.

When the authors examined these subgroups, they found more striking changes in certain profiles. In the small group with hyperoxaluria, urinary oxalate levels dropped from 59.0±11.7 to 28.8±16.0 mg per 24 hours during the P. niruri stage, with a highly significant p value of 0.0002, and remained lower at washout. In those with hyperuricosuria, urinary uric acid decreased from 0.77±0.22 to 0.54±0.07 g per 24 hours, with a p value of 0.0057. The authors state that P. niruri “caused a significant decrease in urinary oxalate and uric acid in patients with hyperoxaluria and hyperuricosuria.”

In hypocitraturic patients, citrate tended to increase over time, but the change did not reach statistical significance, which the paper attributes in part to the limited number of patients. For those with hypercalciuria or hypernatriuria at baseline, there were no significant shifts during the study.

Ultrasound imaging across the three stages showed that many patients experienced a reduction in stone burden. The average number of calculi per patient fell from 3.2±2.0 at baseline to 2.0±2.1 after the P. niruri phase, with a p value of 0.0005, then slightly increased to 2.2±2.2 at washout. Stone size also changed, dropping from 15.6±10.6 to 9.4±8.9 millimeters after P. niruri, then rising modestly to 11.2±11.1 millimeters at washout.

In terms of individual responses, 38 patients (67.8 percent) had fewer stones on ultrasound after using P. niruri, 10 (17.8 percent) had no change, and eight (14.3 percent) had more stones. Some participants reported passing stones or “sandy fragments” in their urine between days 21 and 70 of the P. niruri phase. Summarizing their interpretation, the authors write that “the consumption of P. niruri contributed to the elimination of urinary calculi.”

During the P. niruri period, 66.1 percent of patients reported abdominal pain. Dysuria occurred in 19.6 percent, haematuria in 14.3 percent, and nausea and epigastric pain in 10.7 percent each. Even with these symptoms, no patient stopped the infusion. The authors note that pain and haematuria are common in people with urinary stones and suggest that at least some of these reports may be related to stone passage during the study.

From a safety perspective, serum kidney and liver markers remained stable, aside from the decrease in alkaline phosphatase already described. No acute or chronic toxic effects on organs were detected in this group. In the conclusion of the paper, the authors state that “P. niruri intake is safe and does not cause significant adverse effects or significant serum metabolic changes” under the conditions of their protocol.

Based on the data collected over 26 weeks, the authors present P. niruri as a possible coadjuvant in the management of patients with small kidney stones, especially in those with baseline hyperuricosuria or hyperoxaluria. In these subgroups, the scientific paper reports clear falls in urinary uric acid and oxalate after the P. niruri phase, along with higher urinary magnesium and potassium when all patients are considered together. There was also a decrease in the number and size of upper urinary calculi on ultrasound for most participants.

The discussion section places these results alongside earlier experimental and clinical work on Phyllanthus species. The paper notes prior descriptions of diuretic and hypotensive effects and of changes in the structural appearance of calculi. At the same time, the authors stress several limitations, including the use of ultrasonography instead of repeated computed tomography for stone assessment, which they chose to avoid additional radiation exposure. They also emphasize that “clinical studies with more patients are needed to validate the use of P. niruri in daily practice, particularly in patients with baseline urinary metabolic disorders.”

In their closing remarks, the authors point out that P. niruri is widely available in many countries. They suggest that, if future studies confirm these findings, this plant could help reduce health system costs related to standard drug therapies, which may be difficult for many patients to access for long-term treatment. They are careful to present this as a perspective and call for more research, not as a definitive clinical recommendation.

This 2018 scientific study followed 56 adults with small kidney stones through a 12-week course of Phyllanthus niruri infusion and a 12-week washout period. Within this design, P. niruri did not produce harmful changes in serum metabolic markers and was associated with higher urinary magnesium and potassium, marked reductions in urinary oxalate and uric acid in patients with hyperoxaluria or hyperuricosuria, and fewer and smaller stones on ultrasound in most of the group.

As the authors conclude, “patients with specific urinary metabolic changes such as hyperuricosuria and hyperoxaluria may benefit from ingestion of this tea,” while stressing the need for larger clinical trials to confirm these observations and to clarify how P. niruri might be used as part of prevention strategies for urinary stone disease.