Use of intramuscular midazolam for status epilepticus

Although intravenous (i.v.) administration of antiepileptic drugs is the preferred route of therapy in status epilepticus, intramuscular (i.m.) delivery may provide a valuable alternative when there are obstacles to venous access. Compared to other treatment options such as rectal drug administration, which is as challenging as the i.v. route in a convulsing patient, the i.m. route is easier and less invasive. The two most commonly used first-line anticonvulsants, diazepam and lorazepam, may be administered i.m., but are absorbed from the i.m. site more slowly than midazolam. Midazolam, a fairly new benzodiazepine, is a potent anticonvulsant with a fast onset of effect. Because of its water solubility, midazolam is rapidly absorbed from the injection site and has excellent local tolerability. The pharmacodynamic effects of midazolam can be seen within seconds of its administration, and seizure arrest is usually attained within 5 to 10 min. Case reports and a recent randomized trial that demonstrate the successful use of i.m. midazolam in the termination of epileptic seizures are reviewed.