Febustal is a non-purine selective inhibitorof xanthine oxidase. Febustal is a potent, non-purine, selective inhibitor of xanthine oxidase (X.O) that achieves its therapeutic effect of decreasing serum uric acid by selectively inhibiting xanthine oxidase. Uric acid is the end product of purine metabolism and is generated in the cascade of hypoxanthine-xanthine-furic acid. Both steps in the transformation are catalyzed by xanthine oxidase. Febustal has been shown to potently inhibit both the oxidized and reduced forms of xanthine oxidase. At therapeutic concentrations febuxostat does not inhibit other enzymes involved in purine or pyrimidine metabolism, namely, guanine deaminase, hypoxanthine guanine phosphoribosyltransferase, orotate phosphoribosyltransferase, orotidine monophosphatedecarboxylase or purine nucleoside phosphorylase. Take this medicine in the dose and duration as advised by your doctor. Swallow it as a whole. Do not chew, crush or break it. Febustal 40 mg Tablet may be taken with or without food, but it is better to take it at a fixed time.