All about seizure clusters, or acute repetitive seizures

Seizure clusters are multiple seizures that occur close together in a relatively short time. People need prompt treatment with rescue medication to prevent seizure clusters from progressing.

Seizure clusters are seizures that occur close together and differ from a person’s typical seizure pattern.

They are medical emergencies and require immediate treatment to prevent them from progressing and leading to serious complications, such as status epilepticus.

This article looks at seizure clusters, signs to look for, treatment, and outlook 

What are seizure clusters?

There is no set definition for seizure clusters, but experts generally define seizure clusters as seizures occurring close together, lasting for minutes or up to 2 days.

A seizure cluster varies from person to person. However, a common characteristic is a noticeable increase in seizure activity compared to an individual’s usual pattern.

It can also indicate a pattern that predicts further seizures. For instance, if someone typically experiences more seizures in the days following two or more seizures in a single day, this could be identifiable as a seizure cluster for them.

Various studies have defined seizure clusters as one of these events:

• two to four seizures within 48 hours
• three seizures in 24 hours
• three times the seizure frequency someone would typically experience

How to recognize seizure clusters

Signs of seizure clusters may vary for each individual. Generally, seizure clusters are seizures that occur more frequently than people usually experience them within a certain period, such as:

• two, three, or more seizures in 24 hours
• two or more seizures in 6 hours

People with epilepsy that is severe and not well-controlled may have a higher risk of seizure clusters.

Some may experience an aura or prodrome, which is specific to a seizure cluster.

In other cases, people may recognize they are experiencing a seizure cluster after having two or three seizures with shorter gaps than usual in between each seizure 

Emergency help for seizure clusters

Seizure clusters require immediate medical treatment. Seizure clusters may progress and lead to severe complications, including:

• status epilepticus, a medical emergency where a seizure lasts for 5 minutes or more or when a person does not regain consciousness between seizures
• injuries, such as cuts or fractures due to falling
• death

Diagnosing seizure clusters

There is no clear definition of seizure clusters, so there is no set test or procedure for diagnosing them.

According to a 2022 article, the features of potential seizure clusters can vary between people. This means it is generally up to each healthcare professional to determine if a person has seizure clusters according to their symptoms.

A doctor may assess symptoms and seizure frequency to see if the seizures differ from a person’s usual seizure pattern.

A healthcare professional may decide someone requires treatment for seizure clusters if they experience frequent, increased seizure activity that is different from their usual seizure pattern. 

Treatments for seizure clusters

Using rescue medications can stop a seizure cluster. The main type of rescue medication is benzodiazepines.

Rescue medications include:

• diazepam nasal spray
• diazepam rectal gel
• midazolam nasal spray

Caregivers and family members can administer rescue medications for seizure clusters. These medications may have mild to moderate side effects.

People with epilepsy must have a seizure action plan. A seizure action plan provides family members, caregivers, schools, or workplaces with step-by-step instructions on managing seizure emergencies.

The plan tells people when to use rescue medication and how to administer it. 

Outlook for seizure clusters

Without prompt treatment, seizure clusters may progress to severe complications and may be life threatening.

Prompt treatment with rescue medication may help reduce the risk of injury, hospitalization, and status epilepticus with seizure clusters. Rescue medications, such as benzodiazepines, can stop a seizure cluster. 

Frequently asked questions

What are the dangers of multiple seizures?

Multiple seizures may increase the risk of injury through falls, status epilepticus, or in severe cases, death.

Prompt treatment is important to help prevent multiple seizures from progressing to serious outcomes. 

What is the prevalence of seizure clusters?

Some research suggests the prevalence of seizure clusters may range between 10% to 50% in people with epilepsy.

In a large, population-based sample, there was an estimated prevalence of 3% of seizure clusters in people with epilepsy. However, the prevalence of seizure clusters may be significantly higher in those with drug-resistant or refractory epilepsy. 

Summary

Seizure clusters are seizures that occur close together within a certain time, which is different from a person’s usual seizure pattern.

Seizure clusters require prompt treatment to prevent them from progressing and leading to serious complications.

Rescue medications can help treat them. People with epilepsy must have a seizure action plan so that they and others know how to treat seizures and seizure clusters if they occur.

  Source: medicalnewstoday.com, Nancy Hammond MD, Beth Sissons