SUMMARYRectal diazepam is established as a standard rescue or emergency treatment for seizure or status epilepticus; however, the rectal route of administration has not been universally accepted. To determine if an alternative route of administration of a benzodiazepine was equally effective, we compared a novel midazolam HCl concentrated nasal spray (MDZ-n) with diazepam rectal solution (DZP-r) in the treatment of prolonged seizures in a residential epilepsy center. In 21 adult patients with medically refractory epilepsy, 124 seizureexacerbations were treated by their caregivers, alternatively with 10 mg DZP-r and 10 mg concentrated MDZ-n, two or three treatments with each medication for each patient. No difference was demonstrated in efficacy or time to effect between the two drugs. Common treatment emerging adverse effects were drowsiness for both drugs in more than 50% of the administrations, and short-lasting local irritation after 29% of MDZ-n. No severe adverse events occurred. The nasal spray was preferred to the rectal solution by 16 of 21 caregivers and patients conjointly. MDZ-n was equal to DZP-r with respect to efficacy and side effects in the suppression of seizure exacerbations. The majority of patients and caregivers preferred the nasal spray over the rectal formulation.