mrcem2-1044

You evaluate a 52-year-old man with a painful swollen left big toe. He has a known history of gout and states that this pain is similar to previous flare-ups. He is currently on a daily dose of allopurinol 200 mg and has been taking it for the past year. This is his second episode of acute gout during this time period. He has no significant medical history and is not taking any other medications. He has no known allergies.
What is the MOST suitable next step in management?