Continuation of colchicine for flare prophylaxis and allopurinol for urate lowering is indicated for this patient with tophaceous gout. He is having a good response to colchicine and allopurinol, with a serum urate level currently at the target goal of less than 6.0 mg/dL (0.35 mmol/L), resolution of flares, and reduction in size of tophi (reservoirs of monosodium urate). The American College of Rheumatology currently recommends continuation of flare prophylaxis if there is any evidence of active disease, including flares or tophi as seen in this patient. Hence, both agents should be continued at this time. The guidelines further suggest that in the absence of active disease and once target serum urate is reached, colchicine should be continued for the longer of the following: 6 months; 3 months after reaching target serum urate in a patient without baseline tophi; or 6 months after reaching target serum urate in a patient with baseline tophi that have resolved.

Changing this patient's urate-lowering regimen by adding probenecid or changing allopurinol to febuxostat is unnecessary in this patient who has reached the target serum urate level by taking allopurinol. His gout symptoms have improved, and the tophi have begun to shrink in size. If he was not at goal or was having ongoing flares or resistance of tophi to dissolve on his current regimen, options would be to further increase allopurinol, switch to febuxostat (a newer, more expensive xanthine oxidase inhibitor), or add probenecid.

Colchicine should be maintained at daily dosing because the patient still needs ongoing protection against flares, given the presence of tophi.