Taking a Newer, Faster, Intranasal Route: A Narrative Review of Transitioning to a Less-Invasive Rescue Treatment for Seizure Clusters

Abstract

In the US, 3 rescue treatment options are approved for patients with seizure clusters (ie, acute repetitive seizures), which are intermittent increases of seizure activity. This narrative PubMed review of these 3 treatments examines newer intranasal options that are well suited for adolescent and adult patients who may desire a transition from rectal treatment. Diazepam rectal gel is indicated for patients ≥2 years, diazepam nasal spray for those ≥6 years, and midazolam nasal spray for those ≥12 years. Approvals for diazepam rectal gel and midazolam nasal spray were based on safety and efficacy comparisons with placebo. Approval for diazepam nasal spray was based on results from long-term safety and tolerability studies in addition to its comparable bioavailability to diazepam rectal gel, while also showing less interpatient variability. The safety profiles of diazepam rectal gel and nasal spray are similar, and the medications share safety, warning, and precaution labeling. Thus, patients ≥6 years could be introduced to intranasal diazepam, allowing for continuity of familiar treatment while improving access and comfort. Intranasal midazolam also has a well-characterized safety profile. A proxy for effectiveness is the number of seizure clusters that were treated with a single dose, and these differed in separate, noncomparative studies. The safety and effectiveness of diazepam nasal spray have been examined in multiple subpopulations, whereas patient/caregiver experiences with both approved intranasal formulations have been characterized. Users may prefer nasal administration because it is noninvasive and effective, and provides social advantages, comfort, ease of use, and less variability compared with rectal gel. Nasal sprays are portable and convenient for use in the community (school, work, travel), and self-administration was reported in one study, with patients as young as 11 years old self-administering diazepam nasal spray. These newer, intranasal rescue treatments for seizure clusters provide an alternative to the rectal route.

Keywords: diazepam; epilepsy; midazolam; nasal spray; rectal gel; switch.