Which medication can help prevent the formation of urinary stones?

Potassium citrate plays a significant role in preventing the formation of urinary stones, particularly calcium stones, by increasing the pH of urine (making it more alkaline) and reducing the concentration of calcium oxalate and uric acid in the urine. It helps to dissolve existing stones and prevents further formation by maintaining a proper balance of electrolytes. By raising urinary pH, potassium citrate can also help inhibit the crystallization of various stone-forming substances.

In contrast, calcium supplements may actually increase the risk of stone formation in individuals predisposed to calcium oxalate stones. Furosemide, a loop diuretic, is mainly used for fluid management and does not address the underlying issues contributing to stone formation. Hydrochlorothiazide, a thiazide diuretic, can help reduce calcium levels in urine, but it is not primarily prescribed as a preventive measure for urinary stones. Hence, potassium citrate is the most effective choice among the options to prevent urinary stone formation.