Improving the use of allopurinol in chronic gout: monitoring oxypurinol levels to guide therapy.

Urate-lowering therapy (ULT), adjusted to achieve and maintain a serum uric acid (SUA) of <6 mg/dl, remains the standard of care for the chronic management of gout. New urate-lowering medications are important options; however, these agents should be reserved for patients who do not tolerate or cannot achieve SUA <6 mg/dl on allopurinol. The result of oxypurinol monitoring to guide allopurinol therapy suggests that allopurinol should still be considered first-line ULT for gout.