Multiple sclerosis (MS) is a medical condition in which the immune system attacks the protective myelin covering of nerves within the brain and spinal cord. There is no single, exact way MS affects the body because everyone experiences the disease differently. Some people may have trouble seeing clearly, while others experience arm and leg muscle weakness or a combination of symptoms.

Learn about MS, how it affects the body, treatment options, and more.

The Effects of MS on the Body’s Systems

Nerves send messages to and from the brain, allowing the body and brain to function. They are coated by a protective layer called myelin.

Multiple sclerosis results when the immune system attacks the myelin, and the nerves become damaged. When the nerves are damaged, they can no longer effectively communicate with the brain, leading to challenges that impact different body systems.

The most common MS symptoms affect:

  • Eyes: Blurred vision, double vision, vision loss, changes in seeing colors, and painArms, legs, hands, and feet: Muscle weakness, numbness, prickling, or pins and needlesGeneral body: Difficulty with energy, standing, walking, moving, balance, or coordination

Nervous System

The nervous system includes the brain, spinal cord, and nerves, and is responsible for communication between the body and the brain.

MS affects the nervous system by attacking the layer of myelin that insulates nerves and changes how the nerves send messages to the brain, leading to different results.

Some examples of how MS affects the nervous system are:

  • Neuropathic pain: When MS damages the nervous system, it may result in pain, tightness, burning, or a pins-and-needles sensation.
  • Vision: The optic nerve is part of the nervous system and sends messages between the eyes and brain. MS optic nerve damage can lead to vision loss, eye pain, seeing flashes of light, and other vision changes.
  • Sensations: MS nerve damage can change how messages are sent to the brain from all over the body, causing sensations such as numbness and tingling.
  • Mental health: Many people with MS experience anxiety or depression, mood swings, and other mental health changes.
  • Cognitive function: The brain is part of the nervous system. People with MS may experience difficulties remembering, concentrating, solving problems, and thinking-related symptoms.

Musculoskeletal System

The musculoskeletal system includes the bones, muscles, and the tissues that connect them such as tendons and ligaments.

MS can damage nerves that work with the musculoskeletal system, leading to musculoskeletal symptoms, including:

  • Weakness: Muscles may become weak.
  • Spasms: Muscles may become very tightly squeezed.
  • Spasticity: Muscles may become very stiff and hard to move.
  • Pain: People with MS may experience muscle and joint pain and difficulty with mobility.

Immune System

The immune system includes organs, cells, and proteins such as white blood cells, bone marrow, and lymph nodes.

MS is an autoimmune disease, meaning the immune system works improperly and attacks healthy cells. One of the treatments for MS suppresses the immune system to disrupt this damaging process. A side effect of this treatment is that the immune system is weakened and is less effective at protecting the body from illness.

Digestive System

The digestive system includes the liver, pancreas, gallbladder, and organs that make up the gastrointestinal, or GI, tract, including the stomach and intestines.

MS can affect the digestive system and cause challenges, such as:

  • Constipation, or difficulty passing stool, may occur because nerve damage can prevent muscles from moving waste through the body.
  • Dysphagia, or difficulty swallowing, may occur with MS due to nerve damage affecting the coordination of the muscles in the mouth and throat.
  • Heartburn occurs when stomach acid enters the esophagus and irritates the tissue there. People with MS experience heartburn when nerve damage interferes with the muscle that prevents acid from flowing in the wrong direction.

Reproductive System

The reproductive system includes organs needed to make babies.

The female reproductive system includes:

  • Cervix
  • Fallopian tubes
  • Ovaries
  • Uterus
  • Vagina

The male reproductive system includes:

  • Penis
  • Prostate
  • Testes

Men and women have different reproductive organs, so MS affects them differently. For example, men with multiple sclerosis may experience erectile dysfunction. Women with multiple sclerosis may experience MS symptoms that worsen before their period and during postpartum (after having a baby) or menopause.

Circulatory System

The circulatory system includes the heart, blood vessels, and blood. The lymphatic system is sometimes considered part of the circulatory system and includes bone marrow, white blood cells, lymph nodes, and organs such as the thymus gland.

The link between multiple sclerosis and the circulatory system is not fully understood. However, people with MS are at an increased risk of some circulatory conditions, including:

  • Heart failure - when the heart is no longer able to pump enough blood through the body
  • Ischemic heart disease (IHD) or coronary artery disease (CAD) - when a substance called plaque blocks or prevents blood from flowing to the heart
  • Stroke - when blood is unable to reach the brain

MS Symptoms

MS is an autoimmune disease affecting the nervous system, meaning symptoms can impact the entire body. They are unpredictable, can change over time, and differ for everyone.

MS Treatment

Multiple sclerosis is a lifelong condition. Medications and treatment options are available to manage the disease, prevent it from progressing, and relieve symptoms.

Most Common MS Symptoms

Some of the most common MS symptoms include:

  • Bladder problems (e.g., unable to control)
  • Brain function difficulties
  • Depression
  • Dysesthesia (squeezing sensation)
  • Fatigue
  • Pain
  • Sensations (e.g., numbness, tingling)
  • Spasticity (very tight, stiff muscles)
  • Vision changes
  • Walking (gait) challenges

Treatment options differ depending on the person, their symptoms, and how active the disease is at the time. MS can shift between active phases with increased symptoms called flare-ups and less active or inactive phases with decreased or no symptoms called remission.

Treatment options for multiple sclerosis include:

  • Steroids - used on a short-term basis for flare-ups or phases of active disease
  • Preventive therapies - used to prevent flare-ups, reduce flare-up severity, and prevent the disease from getting worse
  • Symptom management - options that vary depending on the person and their symptoms

In addition to medications for MS, behavior and lifestyle changes may improve symptoms. People with MS who do not smoke or who quit smoking, exercise regularly, and eat healthy foods tend to experience fewer flare-ups and less severe symptoms and may live longer.

Summary

Multiple sclerosis (MS) is a serious, lifelong medical condition when the immune system attacks the nerves in the brain and spinal cord, inhibiting proper communication between the body and the brain. Because of this, people with MS can experience various symptoms. Fortunately, symptoms are treatable with medications and lifestyle changes, and people with MS can live long, happy lives.

A Word From Verywell

Living with multiple sclerosis can be challenging. You may experience both physical and psychological symptoms, as well as social and lifestyle challenges. However, this condition is treatable. Reach out to a healthcare provider for support.

Frequently Asked Questions

  • How does MS affect your legs?
  • MS can cause muscles to become stiff and difficult to move. People with MS may also feel pain or other sensations like numbness or tingling in the legs, or have difficulty walking or standing.
  • What are the most common symptoms of MS?
  • Some of the most common symptoms of MS include bladder problems, fatigue, pain, challenges with brain function, depression, and vision changes. However, everyone experiences MS differently, and with different combinations of symptoms.
  • Can MS cause back and hip pain?
  • MS can cause pain in the back, hips, and other body parts. It can feel like joint pain or tight, painful muscles. However, people can experience MS pain differently.

MS can cause muscles to become stiff and difficult to move. People with MS may also feel pain or other sensations like numbness or tingling in the legs, or have difficulty walking or standing.

Some of the most common symptoms of MS include bladder problems, fatigue, pain, challenges with brain function, depression, and vision changes. However, everyone experiences MS differently, and with different combinations of symptoms.

MS can cause pain in the back, hips, and other body parts. It can feel like joint pain or tight, painful muscles. However, people can experience MS pain differently.