Ketamine add-on Therapy for Established Status Epilepticus Treatment Trial (KESETT)

Inclusion Criteria:

* The patient was witnessed to have a convulsive seizure for greater than 5-minute duration
* The patient received an adequate dose of benzodiazepines. The doses may be divided.
* The last dose of a benzodiazepine was administered 5-30 minutes before study drug administration.
* Continued or recurring seizures in the Emergency Department.
* Age 1 years or older
* Known or estimated weight ≥10 Kg

Exclusion Criteria:

* Known pregnancy
* Prisoner
* Opt-out identification or otherwise known to be previously enrolled in KESETT
* Treatment with a second line anticonvulsant (FOS, PHT, VPA, LEV, phenobarbital, or other agents defined in the MoP) for this episode of SE
* Treatment with sedatives with anticonvulsant properties other than benzodiazepines for this episode of SE(propofol, etomidate, ketamine or other agents defined in the MoP)
* Endotracheal intubation prior to enrollment
* Acute traumatic brain injury clearly precedes seizures
* Scalp injury or burn preventing EEG placement
* Known allergy or other known contraindication to KET or LEV
* Hypoglycemia \< 50 mg/dL
* Hyperglycemia \> 400 mg/dL
* Cardiac arrest / post-anoxic seizures