Published guidelines state that allopurinol doses should be adjusted according to creatinine clearance. We investigated whether such dosing provides adequate control of hyperuricemia.
We studied 250 patients with gout attending rheumatology clinics in South Auckland from 2001 to 2004. Allopurinol dose, creatinine clearance, and serum uric acid (SUA) level were recorded. We analyzed the relationship between recommended allopurinol dose and SUA lowering to <or= 0.36 mmol/l.
For patients taking allopurinol, 70.9% were taking recommended doses, based on published allopurinol dosing guidelines. There were 4 (1.6%) patients with cutaneous hypersensitivity reactions to allopurinol, but none of these patients were taking higher than recommended allopurinol doses. The proportion of patients achieving SUA <or= 0.36 mmol/l was lower in those taking recommended doses, compared with those taking higher than recommended doses (19% vs 38.1%; p < 0.01).
Adherence to published allopurinol dosing guidelines led to suboptimal control of hyperuricemia in this population of patients with gout. Further work is required to clarify the safety and efficacy of allopurinol dose escalation, particularly in patients with renal impairment.