[Inhibitors of xanthine oxidoreductase].

Inhibitors of xanthine oxidoreductase decrease production of uric acid, thus they act as hypouricemic drugs. Allopurinol, a prototypical xanthine oxidoreductase inhibitor, has been widely prescribed for treatment of gout and hyperuricemia. However, severe side effects of allopurinol may occur in patients with renal insufficiency. Recently, novel nonpurine selective inhibitors of xanthine oxidoreductase have been developed as potential alternatives to allopurinol. They have different inhibition mechanisms, utilizing the enzyme structure and the reaction mechanism. Such variation of the inhibition mechanism affects/in vivo/hypouricemic effects of the inhibitors.