OBJECTIVE: To determine the efficacy and safety of sodium bicarbonate, citric acid, sodium citrate, and tartaric acid (compound drug) in comparison to potassium citrate in the treatment of kidney stones.

METHODS: Prospective randomized controlled trial of patients with kidney stones recruited from February to October 2011 at Out-patient Department was conducted. Ninety subjects, consented and eligible, were enrolled in this study. Random allocation of subjects into two groups was done using computer generated randomization. Subjects assigned to group I were treated with the compound drug(12 grams/day); while group II subjects were given potassium citrate(60mEq/day) for 6 weeks. Urinary pH levels were examined weekly and the effect of medical treatment on stone size changes was evaluated by ultrasonography every two weeks in the six-week treatment period. Intention to treat analysis was done with 95% confidence level(CI). Statistical analysis of results was determined using analysis of variance (ANOVA) with multiple repeated measures for between group urinary pH changes and chi square for between groups difference in stone size changes.

RESULTS: A total of 74 subjects completed the study with a dropout rate of 18%, which was mainly due to geographic and financial reasons. Demographic and baseline stone characteristics of both groups were not significantly different. Treatment outcome between the two groups based on stone size changes (in general and both radiolucent and radioopaque stones subgroups) did not show any significant statistic difference. The pH level changes over six-week treatment period between the two groups showed a total mean pH difference of 0.445, (95% CI: 0.213, 0.677), which was statistically significant (P<0.001) in favor of Group I. Both treatment regimens were well-tolerated with very few non-serious medication adverse effects.

CONCLUSION:  Urinary alkalinization with sodium bicarbonate, citric acid, sodium citrate, and tartaric acid is a well-tolerated and highly effective treatment resulting in dissolution of non-obstructing kidney stones and is comparable to the gold standard potassium citrate.