A 70-year-old male with a history of hypertension presents with a fever and severe pain in both his hands. Examination reveals swollen, erythematous, and tender nodules on the joints of his fingers. Arthrocentesis demonstrates negatively birefringent urate crystals in the synovial fluid. Which of the following is most likely to exacerbate this patient’s condition? Image credit: @drugpiter, @twcc.