What is the best treatment for uric acid stones?
Lowering dietary intake of animal protein will reduce the dietary acid load, raising urine pH.
Because most dietary purine comes from animal tissue, lowering animal protein intake will also lower uric acid excretion. The mainstay of therapy to prevent uric acid stone formation is to raise urine pH with alkali.
Potassium citrate is generally preferred. If a patient cannot tolerate potassium salts because of GI side effects or hyperkalemia, then sodium alkali may be used. The goal of therapy is a 24-hour urine pH of 6.0 to 6.5; raising urine pH to higher levels will not provide additional benefit.
Allopurinol is a second-line drug for uric acid stones, used when the patient also has gout or when the patient is unable to take sufficient alkali to raise urine pH higher than 6.0.
Allopurinol should be used in diseases with massive urate overproduction such as Lesch-Nyhan syndrome.
