Diphantoine

Phenytoin sodium (Diphantoine) is an inactive stabilizer for voltage-gated sodium channel .

Phenytoin-d10 is intended for use as an internal standard for the quantification of phenytoin by GC- or LC-MS. Phenytoin is an anticonvulsant agent and active metabolite of fosphenytoin. Phenytoin is formed from fosphenytoin by tissue phosphatases. It inhibits neuronal voltage-gated sodium channels in a voltage-dependent manner. Phenytoin reduces the neuronal firing frequency and decreases the amplitude of excitatory post-synaptic potentials (EPSPs) in electrically stimulated rat corticostriatal slices. It protects against seizures induced by maximal electroshock (MES) in mice. Formulations containing phenytoin have been used in the treatment of tonic-clonic seizures and status epilepticus.

Phenytoin (5,5-Diphenylhydantoin) is a hydantoin derivative and a non-sedative antiepileptic agent with anticonvulsant activity. It potentially acts by promoting sodium efflux from neurons in the motor cortex, reducing post-tetanic potentiation at synapses. This prevents cortical seizure foci from spreading to adjacent areas and stabilizes the threshold against hyperexcitability. Additionally, it appears to reduce muscle spindle sensitivity to stretch, causing muscle relaxation.