Seizures as a Symptom of Multiple Sclerosis

Epilepsy Is Associated with MS, But Is Still a Rare Symptom

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Seizures in MS Patients. ALFRED PASIEKA/SCIENCE PHOTO LIBRARY / Getty Images

Though this may surprise you, people with multiple sclerosis (MS) are more prone to seizures and epilepsy than the general population.

A seizure is basically the result of abnormal or excessive “electrical” activity in the brain, usually in the cerebral cortex. Epilepsy is defined as recurring seizures, which are not due to obvious things, such as fevers or toxic exposures.

This may sound frightening to you.

The good news, however, is that most of these seizures can be successfully treated by a skilled neurologist.

For the nitty gritty on seizures and MS, read this excerpt from UpToDate -- a trusted electronic reference undoubtedly used by many of the physicians who treat patients with MS.

Then, read on for what all of this means for you.

MS and Seizures: Details from UpToDate

"Epilepsy is more common in patients with multiple sclerosis (MS) than in the general population, occurring in 2 to 3% of patients. Convulsions may be either tonic-clonic in nature or partial complex. They generally are benign and transient and respond well to antiepileptic drug therapy or require no therapy. As an example, in a study of 5715 patients with MS, 51 (0.89%) experienced seizure activity. Generalized tonic-clonic seizures were most common (35 patients, 69%), followed by simple or complex partial seizures (11 patients, 22%). Of the 45 patients who received antiepileptic drug therapy, 35 (78%) became seizure free, while 5 (11%) had intractable seizures."

What Do Seizures Feel Like?

People with MS tend to have either tonic-clonic seizures or simple or complex partial seizures, described below:

Tonic-Clonic Seizures

These seizures have two phases:

  • Tonic: The person loses consciousness, the muscles stiffen and the person falls down. The muscles remain rigid and stiff for a short time.
  • Clonic: This is the stage when convulsions (rhythmic flexing and relaxing of the muscles) occur. This stage usually lasts less than two minutes.

Tonic-clonic seizures are sometimes referred to as "grand mal" seizures, although this term is becoming less commonly used. Although they look very dramatic and scary to observers, people experiencing tonic-clonic seizures don’t really feel them as they are happening. They may experience different warning sensations, known as auras. These can include a sudden feeling of anxiety, the sense that everything is fuzzy or dreamlike or a strange smell or taste. The person will typically feel very tired and washed-out after experiencing a seizure.

Simple or Complex Partial Seizures

  • Simple Partial Seizures: While these seizures do not cause the person to lose consciousness, they do make things seem “different” or “off.” For example, people may experience strange emotions or the way things look, sound, feel, smell or taste may be altered. In some cases, the person’s muscles may stiffen up or start twitching, usually just on one side of the face or body.
  • Complex Partial Seizures: These seizures also do not cause a loss of consciousness, meaning people do not “pass out” if they have one. However, this type of seizure does result in a loss of awareness for a short amount of time. People will not remember what happened during this time, nor will they be able to respond to anyone. People having complex partial seizures often stare or move in repetitive ways (rubbing their hands, swallowing or making sounds, for example).

    How Common Are Seizures in People with Multiple Sclerosis?

    As stated in the above excerpt from UpToDate, seizures occur in 2 to 3% of people with MS. It is estimated that less than 1% of people in the general population have seizures.

    How Severe Can Seizures Get in People with MS?

    Seizures in people with MS tend to be mild and cause no permanent damage. The vast majority of people with MS can control or eliminate their seizures with antiseizure medication, and many people do not have to take any medications at all. However, a small percentage of people with MS may have seizures that do not respond to medication at all.

    Additional Points/Information:

    Some paroxysmal symptoms of MS (for example, spasticity, numbness and tingling, dysarthria) can mimic (or be) simple partial seizures. For this reason, it can be difficult to diagnose MS in people experiencing seizures. It can also be difficult to recognize seizures in those already known to have the disease. Your neurologist may have to order an EEG to get a more definitive answer.

    Thankfully, both paroxysmal symptoms and simple partial seizures usually respond to antiepileptic medications.

    Want to learn more? See UpToDate’s topic, "Comorbid problems associated with multiple sclerosis in adults," for additional in-depth, current and unbiased medical information on multiple sclerosis in adults, including expert physician recommendations.


    Olek, Michael J. "Comorbid problems associated with multiple sclerosis in adults." UpToDate. Accessed: December 2008.

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