Midazolam autoinjector pen more effective in treating status epilepticus

Feb 17 2012

Results have just been released from an NIH study conducted at multiple sites, including the University of Kentucky, indicating that an autoinjector pen is a faster and possibly more effective way for emergency medical personnel to treat serious seizures. The study appears in the Feb. 16, 2012 issue of The New England Journal of Medicine.

Typically, when paramedics respond to a patient with status epilepticus (a prolonged seizure lasting longer than five minutes), they attempt to start an IV to deliver anticonvulsant medication to the patient. However, starting an IV in a patient who is experiencing seizures can be challenging for paramedics and waste precious time. An autoinjector - similar to the EpiPen used to treat serious allergic reactions - saves time and delivers needed medication in a quick, consistent way. The autoinjector delivers medication directly into the thigh muscle as an intramuscular injection.

These results are significant, because status epilepticus is a life-threatening emergency that results in approximately 55,000 deaths in the U.S. each year.

The investigators, at UK and other institutions, compared two medicines known to be effective in controlling seizures, midazolam and lorazepam. Both 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.

"Any seizure a patient suffers is a serious medical situation, but seizures that continue more than five minutes are particularly dangerous. We are extremely excited about the results of this study, which will give medical providers and potentially others such as family members of seizure patients a rapid and effective new treatment option to stop dangerous seizures that are not stopping on their own," said Dr. Roger Humphries, chair of the UK Department of Emergency Medicine and principal investigator of the study's UK site.

"Patients with status epilepticus can suffer severe consequences if seizures are not stopped quickly. This study establishes that rapid intramuscular injection of an anticonvulsant drug is safe and effective," said Dr. Walter Koroshetz, deputy director of the National Institute of Neurological Disorders and Stroke (NINDS), part of the NIH, which funded the study.

The investigators said that 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, on-site medical supervision is now required for the safety of the patient.

Source: University of Kentucky