Potassium-magnesium citrate is an effective prophylaxis against recurrent calcium oxalate nephrolithiasis

J Urol. 1997 Dec;158(6):2069-73. doi: 10.1016/s0022-5347(01)68155-2.


Purpose: We examined the efficacy of potassium-magnesium citrate in preventing recurrent calcium oxalate kidney calculi.

Materials and methods: We conducted a prospective double-blind study of 64 patients who were randomly assigned to receive placebo or potassium-magnesium citrate (42 mEq. potassium, 21 mEq. magnesium, and 63 mEq. citrate) daily for up to 3 years. RESULTS. New calculi formed in 63.6% of subjects receiving placebo and in 12.9% of subjects receiving potassium-magnesium citrate. When compared with placebo, the relative risk of treatment failure for potassium-magnesium citrate was 0.16 (95% confidence interval 0.05 to 0.46). Potassium-magnesium citrate had a statistically significant effect (relative risk 0.10, 95% confidence interval 0.03 to 0.36) even after adjustment for possible confounders, including age, pretreatment calculous event rate and urinary biochemical abnormalities.

Conclusions: Potassium-magnesium citrate effectively prevents recurrent calcium oxalate stones, and this treatment given for up to 3 years reduces risk of recurrence by 85%.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Citrates / therapeutic use*
  • Double-Blind Method
  • Drug Combinations
  • Female
  • Humans
  • Kidney Calculi / prevention & control*
  • Magnesium Compounds / therapeutic use*
  • Male
  • Middle Aged
  • Potassium Compounds / therapeutic use*
  • Prospective Studies
  • Recurrence
  • Time Factors


  • Citrates
  • Drug Combinations
  • Magnesium Compounds
  • Potassium Compounds
  • potassium-magnesium citrate