The KESETT study is looking at a new way to treat a serious problem called status epilepticus (SE). SE happens when a person has very long or repeated seizures that do not stop. This can be very dangerous because it can cause breathing problems or hurt the brain if it is not treated quickly. Doctors usually treat SE first with a medicine called benzodiazepines, but these do not work for everyone. When they do not work, doctors use another medicine called levetiracetam, which only helps about half the time. The KESETT study will test if adding another medicine called ketamine to levetiracetam helps more people get better. When a patient comes to Duke and can join the study, they will be put into one of three groups. One group will get levetiracetam alone. The other two groups will get levetiracetam plus ketamine, either in a low dose or a high dose. Doctors will check the patient 15 minutes and 1 hour after the medicine is given. A special headband will be placed on the patient’s head to watch brain activity and look for seizures. The study team will keep checking on the patient for up to 24 hours or until they leave the hospital. After the patient goes home, their part in the study is done.