Further Reduction of Oxalate Excretion by Allopurinol in Stone Formers on Low Purine Diet

Allopurinol may reduce calcium oxalate stone formation. Small elevations in urine oxalate are implicated in calculus production and increased dietary purine increases oxalate excretion1. Oxalate excretion has been reduced by allopurinol in some stone formers2 but trials have been complicated by variations in oxalate excretion with changes in diet and doubts over oxalate methodology. Preliminary studies have shown that allopurinol reduced urine oxalate in normal subjects and the effect was greater with a high purine intake.