Phenobarbital status epilepticus that does not respond to first-line benzodiazepines (lorazepam or diazepam) or to second-line antiepileptic drugs (phenytoin/fosphenytoin, phenobarbital or valproate) is usually considered refractory and requires more aggressive treatment.
Barbiturate anaesthetics, such as pentobarbital and thiopental sodium, are the most frequently used agents and are highly effective for refractory GCSE both in children and adults.
Miller’s anesthesia says the following about Phenobarbital Status Epilepticus –
Treatment of a seizure begins with establishing a patent airway, administering oxygen, and ensuring adequate ventilation. Intravenous anticonvulsant drugs are given to stop the seizure. Commonly used anticonvulsants include lorazepam, Phenobarbital Status Epilepticus, paraldehyde, and phenytoin.
Lorazepam is a rapid and reliable drug used to stop seizures. Boluses of 0.1 mg/kg are given intravenously or rectally when there is no intravenous access. Phenobarbital Status Epilepticus, 5- to 10- mg/kg boluses (maximal dose of 20 mg/kg), also stops seizures. The main complication of lorazepam is respiratory depression when administered in high doses. Giving both phenobarbital and lorazepam together exaggerates the respiratory depression.