Multiple sclerosis (MS) seizures stem from the same abnormal electrical discharges from the brain that cause epilepsy, meaning it is possible to have both MS and epilepsy.

According to the National MS Society, seizures occur in around 2–5% of cases of MS. In comparison, seizure incidence is at about 3% in the general population.

Researchers are not clear about the cause of seizures with MS. But a link exists between seizures and people with more severe MS.

Symptoms vary depending on the type of seizure, but they may include twitching, a loss of consciousness, or involuntary jerking of the arms and legs. Treatment involves the same anti-seizure medications that treat epilepsy in people who do not have MS.

In this article, we discuss the causes, symptoms, and treatment of MS seizures. We also provide first aid information and examine conditions that may have a similar appearance to a seizure.

An X-ray scan of a brain from someone who may have MS and seizures.Share on Pinterest

MS is an inflammatory condition that affects the brain and spinal cord. It happens when the immune system attacks the insulating sheath that covers nerves, leading to lesions that cause various symptoms.

Seizures are not specifically associated with MS, but they occur at a slightly higher rate in people with the condition than in the general population.

A person with MS can have many types of seizures, but the most common include:

  • Focal aware: Previously called simple partial seizures, focal aware seizures start in one area of the brain without causing the person to lose consciousness.
  • Focal impaired awareness: An older term for these is complex partial seizures. They start in one area of the brain and involve a change in consciousness.
  • Focal to bilateral tonic-clonic: Formerly known as secondarily generalized seizures, focal to bilateral tonic-clonic seizures start in one area of the brain and spread to the other side of the brain as a tonic-clonic seizure.

The brain contains gray matter and white matter. Gray matter is in the cortex (the area involved in thinking), and white matter is the part that provides connections for communication between areas of gray matter.

Abnormal electrical discharges coming from the cortex in the gray matter are the cause of epileptic seizures. MS affects white matter. But because some white matter extends into gray matter, some believe that a lesion from MS may affect overlapping gray matter.

Scientists theorize that this may lead to increased excitability in the cortex, which could produce a seizure. The higher incidence of seizures in MS suggests a possible relationship, but it is still under debate, notes a 2019 study.

According to the study, research indicates that the risk of developing seizures with MS increases with the duration of MS. The likelihood may also rise with the number of lesions MS produces in the brain.

The study adds that people who have seizures with MS may experience more severe disability. This is because seizures may increase damage in the brain, which may lead to more disability.

It is possible to have MS and epilepsy. The seizures that occur with MS are epileptic seizures. Some evidence suggests the risk of seizures and epilepsy is three to six times higher in individuals with MS than in the general population.

It is worth noting that the studies included in the linked research above all involved relatively small numbers of participants. This rate also differs from the incidence rates noted by the MS Society.

Symptoms depend on the type of seizure but may include:

  • twitching
  • a strange smell or taste
  • confusion and the inability to respond to stimuli for a few minutes
  • involuntary jerking of arms and legs
  • falling to the ground
  • loss of consciousness

Learn more about the signs and symptoms of a seizure here.

Most people associate seizures with a tonic-clonic seizure, which is the type that involves a person falling, jerking, and becoming unaware of what is going on around them.

For people having a tonic-clonic seizure, the Centers for Disease Control and Prevention (CDC) provide the following first aid recommendations:

  • Ease them to the floor.
  • Turn them to one side, which will help them breathe.
  • Place something soft under their head to help prevent injury.
  • Loosen their tie or any restrictive clothing.
  • Remove their eyeglasses.
  • Do not hold them down or restrict their movements.
  • Do not give mouth-to-mouth breaths.
  • Do not put anything in their mouth.
  • Do not offer food or drink until they are fully alert.

Someone should call 911 or the local emergency number if any of the following apply to the person who has had the seizure:

  • They have difficulty waking or breathing after the seizure.
  • They have an injury.
  • They have another seizure soon after the first one.
  • They have a health condition, such as heart disease or pregnancy.
  • The seizure occurs while they are in water.
  • The seizure lasts longer than 5 minutes.

Learn more about what to do if someone you know has a seizure.

The Multiple Sclerosis Foundation notes that treatment for seizures in MS uses antiepileptic drugs that control most seizures, such as:

  • phenytoin (Dilantin)
  • carbamazepine (Tegretol)
  • valproic acid (Depakote)
  • lamotrigine (Lamictal)
  • levetiracetam (Keppra)

Antiepileptic drugs can cause a number of side effects that are also typical symptoms of MS. Anyone who experiences any of the following symptoms should tell their doctor. This is so that the doctor can try and work out if the symptoms are due to the medication or the worsening of MS:

  • foggy thinking
  • dizziness
  • fatigue
  • tingling
  • trouble sleeping

Stopping or reducing the use of antiepileptic drugs should always be done under the supervision of a doctor. Suddenly stopping the use of this medication can trigger a seizure.

Sometimes a person with MS may have an experience that resembles a seizure, but which is actually a manifestation of their condition, known as a paroxysmal symptom. A paroxysmal symptom is a sudden symptom that lasts a few seconds to a few minutes.

Paroxysmal symptoms may take many forms. For example, one form that may resemble a seizure is spasms, such as twitching or kicking a leg. Other forms include:

  • an altered sensation that affects the skin, such as numbness or tingling
  • shooting pains in the arms or legs
  • difficulty swallowing
  • weakness, which can cause a fall or unsteadiness
  • slurred speech
  • lack of coordination
  • brief freezing of movements

The cause of paroxysmal symptoms is an abnormal electrical signal in a nerve of the brain or spinal cord that MS damages, which differs from the cause of an epileptic seizure. Although the cause is not epilepsy, doctors may treat it with antiepileptic medication, which often helps reduce the symptoms.

Aside from paroxysmal symptoms, several other conditions can resemble seizures, including:

  • fainting spells, which can cause a seizure in addition to the loss of consciousness
  • low blood sugar, which can cause episodes of confusion
  • sleep disorders, such as narcolepsy, which is falling asleep at inappropriate times
  • movement disorders, such as nervous tics or tremors
  • a migraine headache, which may cause confusion
  • non-epileptic seizures, which look like epileptic seizures but are associated with psychiatric conditions, such as post-traumatic stress disorder

Unlike paroxysmal episodes, antiepileptic drugs cannot help with treating these conditions. Doctors will recommend appropriate treatment depending on what the cause is.

MS seizures are not common. Research suggests that the risk of seizures may be higher in people who have had MS for a long duration or have a greater number of brain lesions.

Individuals with MS may sometimes have sudden, brief bursts of spasms or other problems called paroxysmal symptoms. These are not seizures, although they may resemble them.

Doctors treat the seizures of MS with standard antiepileptic drugs such as phenytoin (Dilantin). If a seizure lasts longer than a few minutes, someone should call 911 for immediate medical attention.