Should patients continue to seize even after administration of a benzodiazepine (i.e. lorazepam, diazepam) plus phenytoin, additional high-dose phenytoin should first be considered.
While the standard loading dose for IV phenytoin is 10-20 mg/kg, it is recomended that up to 30 mg/kg of phenytoin be given for refractory status epilepticus prior to using another anti-epileptic, such as phenobarbital, pentobarbital infusion, or propofol infusion.
References
Osorio et al. "Treatment of refractory tonic-clonic status epilepticus with pentobarbital anesthesia after high dose phenytoin." Epilepsia. 1989;30:464-71.
Working Group on Status Epilepticus. Treatment of convulsive status epilepticus: recommendations of the Epilepsy Foundation of America's working group on status epilepticus. JAMA. 1993;270:854-859.
