STABLE PHARMACEUTICAL COMPOSITION OF 3-(HYDROXYMETHYL)-5,5-DIPHENYLHYDANTOIN DISODIUM PHOSPHATE ESTER

摘要

Described is a stable pharmaceutical composition of 3-(hydroxymethyl)-5,5-diphenylhydantoin disodium phosphate ester, the produg of 5,5-diphenylhydantoin (phenytoin) a commonly used drug for the treatment and management of epilepsy and other types of convulsive states. It has been found that degradation of the produg to phenytoin can be controlled by controlling the pH of the composition. Controlling the pH to between 8.3 to 9.4 results in the production of diphenylglycinamide as the primary degradant and minimization of degradation to phenytoin. If the pH is maintained at a lower or higher value, then the degradation pattern changes, with earlier than expected product failure.