NCIt definition : A heterocyclic organic compound with anticonvulsant property. Although the mechanism
of action is not well established, mephenytoin potentially promotes sodium efflux
from neurons in motor cortex, and stabilizes the threshold against hyperexcitability
caused by excessive stimulation. Thus this agent reduces the membrane sodium gradient
and prevents cortical seizure signal spreading. It may cause blood dyscrasias, therefore,
this agent was only used after other less toxic anticonvulsants had failed.;