Parkinson’s disease and multiple sclerosis are neurodegenerative diseases that affect your brain and spinal cord.

Multiple sclerosis occurs when your immune system attacks cells that cover your nerves. Parkinson’s is caused by the loss of dopamine-producing cells in a part of your brain called the substantia nigra.

Keep reading as we look at the similarities and differences between these two conditions and examine whether there’s a link between them.

Here’s a brief look at some of the main similarities and differences between Parkinson’s disease and multiple sclerosis.

Parkinson’s diseaseMultiple sclerosis
Symptoms• Primarily causes tremors, slow movement, muscle stiffness, and balance problems• Symptoms vary significantly and are unpredictable
• Commonly include fatigue, trouble walking, and vision problems
Causes• Loss of dopamine-producing cells in your brain
• Genetic and environmental factors contribute
• Loss of the myelin cells that surround nerves in your brain and spinal cord due to an autoimmune reaction
• Genetic and environmental factors contribute
Diagnosis• No single test can be used
• Diagnosis is made clinically by a doctor based on signs and symptoms
• A DaTscan may be used to show evidence of loss of dopamine-producing cells
• No single test can be used
• Diagnosis is made primarily by ruling out other potential conditions and examining your signs and symptoms
Treatment• Medications to control symptoms
• Lifestyle changes
• Supportive therapies to improve problems with movement
• Some people don’t need any particular therapy
• Primarily treated with corticosteroids to control inflammation and medications to slow disease progression

The exact cause of multiple sclerosis and Parkinson’s is not clear, and scientists are still trying to figure out whether they’re linked.

Multiple sclerosis

Multiple sclerosis occurs when your immune system attacks myelin cells in your brain and spinal cord. These cells create a protective layer around your nerves and increase the speed that electrical information can travel.

When your immune system attacks myelin, it causes nerve inflammation. Over time, repeated attacks can lead to permanent damage to your nerves.

It’s still not clear why some people develop multiple sclerosis, but some risk factors have been identified:

  • Genetics. People with a sibling or parent with multiple sclerosis have about a 2 to 3 percent chance of developing it too.
  • Teenage obesity. People who have obesity as teenagers are at a higher risk of developing multiple sclerosis later in life.
  • Biological sex. Women are about 2 to 3 times more likely to develop multiple sclerosis than men.
  • Epstein-Barr virus infection. It’s thought that infection from the Epstein-Barr virus, which causes mononucleosis, might trigger immune activity that leads to multiple sclerosis in some people.
  • Smoking. Smoking increases your risk of developing multiple sclerosis.
  • Vitamin D deficiency. Countries that get less sunlight tend to have higher rates of multiple sclerosis.

Parkinson’s disease

Parkinson’s disease is caused by the loss of cells that produce dopamine in a part of your brain called the substantia nigra. Dopamine is a neurotransmitter that plays many roles in your body, such as coordinating movement.

It’s thought that a combination of genetic and environmental factors are responsible for the development of Parkinson’s:

  • Genetics. Genetics are thought to cause about 10 to 15 percent of Parkinson’s cases.
  • Chemical exposure. Exposure to certain chemicals such as pesticides, herbicides, and fungicides are thought to contribute to the development of Parkinson’s.
  • Age. Parkinson’s becomes more common with age.
  • Occupation. People in some occupations such as welders and agriculture workers may be at an increased risk of Parkinson’s disease, but more research is needed.

Parkinson’s and multiple sclerosis can share some of the same symptoms, such as:

Multiple sclerosis symptoms

Symptoms of multiple sclerosis vary quite a bit between people but may include:

Parkinson’s symptoms

Parkinson’s typically causes:

Other symptoms often include:

To make a Parkinson’s or multiple sclerosis diagnosis, doctors review your medical history and run a variety of tests, such as a:

  • neurological exam
  • physical exam
  • blood tests
  • imaging

Multiple sclerosis diagnosis

Doctors can’t use any single test to diagnosis multiple sclerosis. According to the National Multiple Sclerosis Society, to make a diagnosis your doctor must:

  • find evidence of damage in two separate parts of your central nervous system among your brain, optic nerves, and spinal cord AND
  • find evidence that the damage occurred at different times AND
  • rule out all other possible conditions

Specific tests your doctor may perform include:

  • examining your medical history
  • performing a physical and neurological exam
  • MRI scan
  • spinal fluid analysis
  • blood tests

Parkinson’s diagnosis

Parkinson’s disease is one of the few medical conditions where a formal diagnosis can be made clinically based on your signs and symptoms during a physical and neurological exam. For your doctor to make a diagnosis, you need to have 2 out of 3 of the following:

  • shaking or tremors
  • slowness of movement
  • muscle stiffness

One of the clearest signs of Parkinson’s is a positive response to the medication Levodopa.

Imaging techniques such as single photon emission computed tomography scans and magnetic resonance imaging may help rule out other conditions.

A dopamine transporter scan (DaTscan) may be used to identify loss of dopaminergic uptake in a part of your brain called the basal ganglia. However, interpreting the results can be difficult, and it isn’t routinely used.

Neither Parkinson’s nor multiple sclerosis currently have a cure. Treatment aims to slow progression and minimize symptoms.

Multiple sclerosis treatment

Many people with mild forms of multiple sclerosis do well without therapy. Treatment options include:

  • Corticosteroids. Corticosteroids may be prescribed to treat inflammation, but they don’t slow disease progression.
  • Plasma exchange. If your symptoms are severe and don’t respond to steroids, your doctor may recommend a plasma exchange. This involves separating plasma cells from your blood, mixing them with a solution, and reinjecting them back into your body.
  • Medications to modify disease course. A number of drugs are approved by the Food and Drug Administration (FDA) to prevent relapses or multiple sclerosis progression. Learn more about multiple sclerosis medications.
  • Other medications. Other medications may be prescribed to target specific symptoms, such as fatigue, muscle stiffness, or pain.
  • Physical therapy. A physical therapist can help you stretch and strengthen your muscles to improve your strength, balance, and mobility.

Parkinson’streatment

Medications often help control Parkinson’s symptoms. The primary medications used to treat Parkinson’s are:

A type of surgical procedure called deep brain stimulation is sometimes used to treat advanced Parkinson’s.

Supportive therapies such as physiotherapy and occupational therapy can help you improve movement and maintain independence as long as you can. Speech and language therapy can help you target speech problems.

Parkinson’s and multiple sclerosis are both neurological diseases that primarily affect your brain and spinal cord. Although they can produce some similar symptoms, they require different treatments, and a proper diagnosis is necessary.

Diagnosis for both conditions often starts by visiting your family doctor, who may refer you to a doctor who specializes in the brain and nerves, called a neurologist.