Does urinary alkalinization help with nephrolithiasis (kidney stones)?

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From the Guidelines

Yes, urinary alkalinization can help with certain types of kidney stones, particularly uric acid stones, by increasing the pH of urine and making it less acidic, which helps dissolve existing uric acid stones and prevents new ones from forming, as recommended by the American College of Physicians guideline 1. For urinary alkalinization, potassium citrate is commonly prescribed, with a typical dose of 10-20 mEq taken orally 2-3 times daily, as determined by a healthcare provider based on individual factors. To implement this:

  • Take the medication as prescribed with meals.
  • Increase fluid intake to at least 2-3 liters per day.
  • Monitor urine pH using test strips, aiming for a pH between 6.5 and 7.0.
  • Continue treatment long-term to prevent stone recurrence. Urinary alkalinization works by increasing the pH of urine, making it less acidic, which helps dissolve existing uric acid stones and prevents new ones from forming, and also inhibits calcium stone formation by reducing calcium excretion and increasing citrate excretion, which is a natural stone inhibitor, as supported by the American Urology Association guideline 1. While effective for uric acid stones, this approach may be less beneficial for calcium oxalate stones, the most common type, and always consult with a healthcare provider for personalized treatment, as the effectiveness depends on the specific type of kidney stone, as noted in the Annals of Internal Medicine guideline 1.

From the FDA Drug Label

The effect of oral Potassium Citrate therapy in a non-randomized, non-placebo controlled clinical study of five men and four women with calcium oxalate/calcium phosphate nephrolithiasis and documented incomplete distal renal tubular acidosis was examined Potassium Citrate therapy was associated with inhibition of new stone formation in patients with distal tubular acidosis. All patients had a reduced stone formation rate. Over the first 2 years of treatment, the on-treatment stone formation rate was reduced from 13±27 to 1±2 per year. The stone formation rate was reduced in all groups as shown in Table 1. While on Potassium Citrate treatment, urinary pH rose significantly from a low value of 5.3 ± 0.3 to within normal limits (6.2 to 6. 5).

Urinary alkalinization with potassium citrate helps with nephrolithiasis (kidney stones) by:

  • Inhibiting new stone formation
  • Reducing stone formation rate
  • Increasing urinary citrate excretion
  • Increasing urinary pH 2

From the Research

Urinary Alkalinization for Nephrolithiasis

  • Urinary alkalinization is a treatment approach for nephrolithiasis, specifically for uric acid kidney stones 3, 4, 5, 6, 7
  • The goal of urinary alkalinization is to increase the urinary pH to a range of 6-6.5, which helps to prevent uric acid stone formation 6
  • Potassium citrate and potassium bicarbonate are commonly used alkali agents for urinary alkalinization, with potassium citrate being preferred due to its potential to avoid calcium salt precipitation 4, 5, 6

Efficacy of Urinary Alkalinization

  • Studies have shown that urinary alkalinization with potassium citrate and potassium bicarbonate can effectively dissolve uric acid stones and prevent stone recurrence 3, 4, 6, 7
  • A study of 120 patients with uric acid lithiasis found that treatment with potassium citrate resulted in complete stone dissolution in 88% of cases and prevented stone recurrence in 45 patients 3
  • Another study of 8 patients with radiolucent stones found that treatment with potassium citrate and potassium bicarbonate resulted in complete stone dissolution in 3 patients and partial dissolution in 5 patients 4

Safety and Tolerability

  • Urinary alkalinization with potassium citrate and potassium bicarbonate has been shown to be well-tolerated and safe, with minimal side effects reported 3, 4, 7
  • A study of 24 patients with uric acid nephrolithiasis found that 3 patients did not tolerate the initiation of dissolution therapy, but the remaining 21 patients had minimal complications and no serious side effects 7

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Medical treatment of uric acid kidney stones.

Canadian Urological Association journal = Journal de l'Association des urologues du Canada, 2024

Research

Dissolution of radiolucent renal stones by oral alkalinization with potassium citrate/potassium bicarbonate.

Archivio italiano di urologia, andrologia : organo ufficiale [di] Societa italiana di ecografia urologica e nefrologica, 2009

Research

Pharmacologic treatment of uric acid calculi.

The Urologic clinics of North America, 1987

Research

Urinary alkalization for the treatment of uric acid nephrolithiasis.

Archivio italiano di urologia, andrologia : organo ufficiale [di] Societa italiana di ecografia urologica e nefrologica, 2010

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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