Pharmacology: Febuxostat is FDA approved non-purine, selective inhibitor of xanthine oxidase approved for the chronic management of hyperuricemia in patients with gout. It is not recommended for asymptomatic or secondary hyperuricemia, nor it is indicated for treatment of acute gout. Febuxostat lowers serum uric acid levels by blocking xanthine oxidase - the enzyme responsible for uric acid production. Xanthine oxidase breaks down hypoxanthine (a natural-occurring purine derivative) to xanthine, and then to uric acid.