Autoinjectors Key to Stopping Seizures

LEXINGTON, Ky. (April 10, 2012) - The following column appeared in the Lexington Herald-Leader on Sunday, April 8.

Autoinjectors Key To Stopping Seizures

By Dr. Roger Humphries

New National Institutes of Health-sponsored research by the University of Kentucky and other institutions indicates that intramuscular injection of medication allows paramedics to stop life-threatening seizures faster than traditional intravenous (IV) treatment.

Status epilepticus — or people having a seizure that won’t stop — is a life-threatening emergency that results in approximately 55,000 deaths in the U.S. each year. When paramedics and doctors treat these seizures, the standard treatment is to use IV medications. However, it is very difficult to start an IV when someone is having a seizure.

Intramuscular injection using an auto injector pen (similar to an epi-pen used to treat allergic reactions), has now been demonstrated to be an effective way of stopping seizures faster.

Any seizure a patient suffers is a serious medical situation, but seizures that continue more than five minutes are particularly dangerous.

Investigators at UK and other institutions compared two medicines known to be effective in controlling seizures, midazolam and lorazepam. The trial started in 2009 and completed enrollment in June 2011. It involved more than 79 hospitals, 33 emergency medical services agencies, more than 4,000 paramedics and 893 patients ranging in age from several months old to 103.

Both medicines are benzodiazepines, a class of sedating, anticonvulsant drugs. Midazolam was a candidate for injection because it is rapidly absorbed from muscle. Lorazepam must be given by IV. The study found that 73 percent of patients in the group receiving midazolam via autoinjector were seizure-free upon arrival at the hospital, compared to 63 percent of patients who received IV treatment with lorazepam.

Patients treated with midazolam were also less likely to require hospitalization than those receiving IV lorazepam. Among those admitted, both groups had similarly low rates of recurrent seizures.

Patients with status epilepticus can suffer severe consequences if seizures are not stopped quickly. This study established that rapid intramuscular injection of an anticonvulsant drug is safe and effective.

Because of the nature of the approval process for new drugs, the autoinjector treatment is not currently available. But in the future, it may become the standard treatment for prolonged seizures.

While autoinjectors might someday be available for use by epilepsy patients and their family members, more research is required. Because of the strong sedative effect of midazolam, medical supervision is now required for the safety of the patient.

Dr. Roger Humphries is Chair of Emergency Medicine at the University of Kentucky.