الفهرس 
A Pharmaceutical study on certain antigout drug for oral administration
ContentsOnly 14 pages are availabe for public view
 |  | from | 186 |  |  |
| | | from | 186 | | |
Abstract
Febuxostat is a novel, potent, non-purine, selective xanthine oxidase inhibitor which is preferred than allopurinol in reducing the serum uric acid levels and treatment of gout. It works by noncompetitively blocking the molybdenum pterin center, which is the active site on xanthine oxidase. Xanthine oxidase is needed to successively oxidize both hypoxanthine and xanthine to uric acid. Hence, FXS inhibits xanthine oxidase, therefore reducing the production of uric acid. It inhibits both oxidized and reduced forms of xanthine oxidase, because FXS cannot easily be displaced from the molybdenum pterin site. It is a BCS class II compound which has poor aqueous solubility, its oral bioavailability is moderate (<49%) due to its low aqueous solubility and its exposure to enzymatic degradation in both intestine and liver. Rapid onset of action is required to provide fast relief in treatment of gout. Thus, it is necessary to enhance the aqueous solubility and dissolution rate of Febuxostat to obtain faster onset of action, minimize the variability in absorption and improve its oral bioavailability. Over recent years lipid based formulations have gained much attention, with particular emphasis on selfnanoemulsifying drug delivery systems to improve the solubility of poorly water-soluble drugs and enhance their bioavailability. Selfnanoemulsifying systems are isotropic mixtures of oils, surfactants or alternatively, one or more hydrophilic solvents & cosurfactants which emulsify spontaneously when introduced into aqueous phase under gentle agitation to produce fine oil-in-water emulsions, depending upon the size of globules of the formed emulsions