Seizure cluster: Definition, prevalence, consequences, and management.

PURPOSE: To summarize definitions, prevalence, risk factors, consequences, and acute management of seizure clusters using rescue medications.

METHODS: We searched MEDLINE for studies that assessed definitions, clinical characteristics, outcomes, and use of rescue medication for aborting seizure clusters.

RESULTS: Different clinical and statistical definitions for seizure clusters have been proposed, including: ≥3 seizures in 24 h, ≥2 seizures in 24 h, and ≥2 seizures in 6 h. Most studies of seizure clusters have been conducted in tertiary epilepsy centers, with refractory epilepsy patients. Patients with severe and poorly controlled epilepsy are more likely to experience seizure clusters. Seizure clusters can result in increased health care utilization and have negative impact on the quality of life of patients and caregivers. Use of benzodiazepine rescue medications in acute management of seizure clusters can help avoid progression to status epilepticus and reduce emergency room visits. Rescue medications are underutilized in seizure clusters. Currently, rectal diazepam gel is the only FDA approved rescue medication for seizure clusters. In addition, buccal midazolam is approved in European countries for treatment of prolonged seizures. However, various non-rectal non-IV benzodiazepines are safe and effective in treating acute seizures and clusters. Most patients and caregivers preferred non-rectal routes.

CONCLUSION: Identifying patients that are at high risk for seizure clusters, providing them with formal action plans and educating them about use of rescue medication for seizure clusters can help ameliorate the outcomes in this group of epilepsy patients.