MS and the vagus nerve may affect each other. Preliminary animal research suggests vagus nerve stimulation (VNS) may help reduce certain processes, such as inflammation, that contribute to MS. However, more evidence is necessary.

MS is an autoimmune disorder affecting the central nervous system (CNS). In MS, the immune system mistakenly attacks the myelin sheath, a protective layer around the nerve fibers.

The condition causes inflammation, which can affect how the vagus nerve functions. Dysregulation in systems related to the vagus nerve may also trigger MS symptoms.

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Some researchers believe MS can affect the vagus nerve and that the vagus nerve may affect processes involved in MS.

With MS, the immune system mistakenly attacks the myelin sheath, a protective layer that surrounds nerve tissue. This sheath allows electrical signals to travel along nerve cells efficiently. Demyelination (damage to the myelin sheath) can disrupt these signals, affecting various bodily functions.

The vagus nerve runs from the brainstem through the chest and abdomen alongside the heart and structures of the digestive system. It stimulates the release of neurotransmitters and hormones that affect organs throughout the body.

MS may affect the vagus nerve through inflammation and demyelination.

Inflammation

The immune response that mistakenly attacks the myelin sheath in people with MS involvesTrusted Source the release of pro-inflammatory cytokines. These are proteins that immune cells, such as T cells, release to trigger or increase inflammation.

Overactive pro-inflammatory cytokines can affectTrusted Source the vagus nerve, disrupting the transmission of signals along the nerve. This may contribute to MS symptoms, such as fatigue.

Because the vagus nerve acts as an interface between the gut and the brain, some researchers believe there may be a connection between MS and the vagus nerve related to communication between these areas.

A 2023 animal study suggests that alterations in gut inflammation and microbiota could contribute to CNS inflammation, which may damage the myelin sheath.

Researchers in a 2021 review suggest this may occur if the vagus nerve transmits information from the gut to the brain that results in activation of immune cells, such as T cells, in the CNS.

The immune response may cause CNS inflammation, which can lead to demyelination. This damage can cause MS symptoms, such as:

  • cognitive changes
  • vision problems
  • gait and walking difficulties

Demyelination

As well as causing the immune system to attack the myelin sheath, MS prevents the CNS from effectively replacing damaged myelin. The lack of a protective later impairs nerve function.

Sometimes nerve fibers, called axons, also sustainTrusted Source damage in MS. When this happens, the symptoms are permanent.

In a 2023 study involving mice, researchers found that the activity of the vagus nerve affected gut bacteria, which secondarily increase inflammation in the brain. This suggests a possible a link between vagus nerve function, the gut microbiome, and CNS inflammation.

This may occur due to inflammation that the vagus nerve triggers during communication between the gut and the brain. However, more research is necessary to understand this connection.

Vagus nerve stimulation (VNS) involves electrical stimulation of the vagus nerve via a surgically implanted device called a pulse generator. The device, which a doctor implants under the skin of the chest, delivers calibrated electrical impulses that travel along the vagus nerve to the brain.

The Food and Drug Administration (FDA) approvesTrusted Source VNS treatment for various conditions, including epilepsy and depression.

VNS is not a proven or approved treatment for autoimmune and inflammatory disorders, including MS. However, research into VNS as a potential treatment for these conditions is ongoing.

More research is necessary to determine the efficacy of VNS as a treatment for MS. However, current research is promising.

A 2024 animal study suggests VNS could reduce the activation of cells that cause neuroinflammation and prevent myelin repair in MS. This could help prevent the demyelination that can lead to the development of permanent and progressive MS symptoms.

Another animal study also suggests that VNS warrants further research as a potential MS therapy in humans, and cites studies that indicate it may help reduce specific symptoms, including tremors and difficulty swallowing.

More research is necessary to determine how effective and safe VNS may be as an MS treatment.

Some people may experienceTrusted Source side effects from the treatment, which often improve over time. These include:

Rarely, the implantation of the pulse generator may cause complications, such as:

There is currently no cure for MS. However, treatment can help slow the condition’s progression and reduce the symptoms.

Doctors typicallyTrusted Source treat MS with medications, including disease-modifying therapies. These medications suppress or change certain cells in the immune system to prevent it from attacking the myelin sheath.

During an MS flare-up, a doctor may also prescribe corticosteroids to reduce inflammation. Often, physical or occupational therapy can help with improving strength and adapting to MS-related changes in physical ability.

Learn more about occupational therapy for MS.

People who experience possible symptoms of MS should contact a doctor. Early symptoms oftenTrusted Source include:

A doctor will determine whether MS is causing the symptoms and discuss treatment options.

Multiple sclerosis (MS) may affect the vagus nerve, which some researchers believe is also involved in certain processes that contribute to MS.

Research suggests the vagus nerve may be involved in inflammation and demyelination (damage to the myelin sheath) in people with MS. This could be due to communication between the gut and the central nervous system (CNS) via the vagus nerve, which may help regulate CNS inflammation.

More research is necessary to understand possible links between the vagus nerve and MS. However, animal studies suggest that vagus nerve stimulation may have potential benefits as an MS treatment in humans.