A seizure is a sudden surge of unusual electrical activity in the brain. Seizures can cause changes in movement, behavior, and awareness.

While some seizures have obvious symptoms, others are subtler and harder to recognize.

Some symptoms of a seizure include:

  • changes to sense of smell, sound, or taste
  • confusion
  • dizziness
  • feelings of fear, panic, or déjà vu
  • headache
  • nausea
  • numbness and tingling
  • staring or unresponsiveness
  • loss of consciousness
  • uncontrollable jerking movements, shaking, or twitching
  • visual disturbances

A seizure typically lasts from 30 seconds to 2 minutes, but they can last longer.

Some people with multiple sclerosis (MS) experience seizures. Experts aren’t sure why it happens, but it may have something to do with how MS affects the brain.

Read on to learn more about MS-related seizures as well things that might be mistaken for seizure symptoms in people with MS.

Seizures affect between 2 and 5 percent of people with MS, so it’s not a very common symptom. For comparison, about 3 percent of people in the general population experience seizures.

They can occur as part of a disease relapse or independent of a relapse. Sometimes, a seizure is the first noticeable sign of MS.

There are many types of seizures. The most common types for people with MS are:

No one’s sure exactly what causes seizures in people with MS. But a 2017 study found a close link between chronic demyelination and seizures.

Seizures are usually associated with epilepsy. This is a condition that causes unpredictable, recurring seizures. It’s usually diagnosed when someone’s had two seizures with no apparent cause.

It’s possible to have both MS and epilepsy. In fact, the risk of epilepsy is about three times higher for people with MS than for others.

Some other potential causes of seizures include:

  • high or low sodium or glucose levels
  • excessive alcohol consumption
  • brain infection
  • brain tumor
  • certain medications
  • head trauma
  • high fever
  • lack of sleep
  • recreational drug use
  • stroke

Several things can mimic the signs of a seizure, especially in people with MS.

Paroxysmal symptoms

MS can damage nerves in the brain, interrupting electrical signals. This causes a range of symptoms known as paroxysmal symptoms. Similar to seizures, paroxysmal symptoms come on suddenly and don’t last for long.

Paroxysmal symptoms include:

  • inability to move
  • lack of coordination
  • muscle contractions, or spasms
  • slurring of speech
  • stabbing sensations, particularly in the face
  • unusual sensations such as burning, itching, numbness, and tingling
  • weakness

Sometimes, paroxysmal symptoms happen when you’re having an MS relapse. But they can also appear between relapses.

Triggers for paroxysmal symptoms can include:

  • emotional stress
  • fatigue
  • hyperventilation
  • sudden movement or change in body positioning
  • temperature change
  • touch

While paroxysmal symptoms are different from seizures, they do respond to anticonvulsants. These are medications traditionally used to treat epilepsy.

Other conditions resembling seizures

Other things that can sometimes look or feel like a seizure include:

If you’ve had what feels like a seizure that lasts for more than five minutes, seek emergency medical treatment. You should also get emergency care if you think you’ve had a seizure and:

  • it’s your first time having a seizure
  • you’re pregnant
  • you have diabetes
  • you have a high fever
  • you have heat exhaustion
  • you immediately had a second seizure
  • you sustained an injury during a seizure

Having one seizure doesn’t necessarily mean you’ll have another. It could be a one-time event. But if you have MS and have never had a seizure before, make an appointment with your doctor. They can help to determine whether you’ve actually had a seizure and what might have caused your symptoms.

Here are a few tips to prepare for your appointment:

  • Write down what it felt like when you experienced seizure-like symptoms, including the moments before and after.
  • Note the date and time of your symptoms, as well as what you were doing just before symptoms began.
  • List any other unusual symptoms you’ve had lately.
  • Tell your doctor if you have other conditions, such as diabetes.
  • List all your medications, even those that aren’t related to MS.

People with MS can have seizures, but they aren’t always directly related to MS. There are also several conditions that can cause symptoms similar to those of a seizure. If you have MS and think you’ve had a seizure, make an appointment with a doctor or neurologist. They can help you figure out what caused your symptoms and come up with a treatment plan, if needed.