Patent ID: 8545885

Claim:
A pharmaceutical composition comprising N-ethyl-N-phenyl-1,2,-dihydro-4-hydroxy-5-chloro-1-methyl-2-oxoquinoline-3-carboxamide or a pharmaceutically acceptable salt thereof, at least 0.001 wt % of an oxidation reducing agent, and a pharmaceutically acceptable carrier, or a pharmaceutical formulation in tablet form wherein the tablet comprises a core comprising N-ethyl-N-phenyl-1,2,-dihydro-4-hydroxy-5-chloro-1-methyl-2-oxoquinoline-3-carboxamide or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier and a coating which inhibits oxygen from contacting the core, or a sealed package comprising the pharmaceutical composition, the pharmaceutical composition and an oxygen absorbing agent, the pharmaceutical formulation, or the pharmaceutical formulation and an oxygen absorbing agent.