Myositis is a progressive inflammation of the muscles that may also manifest with a skin rash. Medications and some exercises can relieve symptoms, but you may need to try a few strategies before finding the one that works long term.

Myositis is a rare disease that can be difficult to diagnose. It affects both children and adults.

Symptoms of myositis may appear rapidly or gradually over time and often include muscle pain and soreness, fatigue, trouble swallowing, and difficulty breathing. The cause of the condition has yet to be established.

Although many symptoms overlap, the five types of myositis have slightly different presentations and contributing factors.

Types of myositis include:

  • dermatomyositis
  • inclusion-body myositis
  • juvenile myositis
  • polymyositis
  • toxic myositis

Dermatomyositis

Dermatomyositis (DM) causes skin rashes that may appear as red or purple spots (depending on your skin color) in the shape of the heliotrope flower.

The myositis rash may develop on the eyelids, face, chest, neck, and back. It could also affect joints such as knuckles, elbows, knees, and toes.

Muscle weakness usually follows the development of the heliotrope rash.

Other symptoms of DM may include:

  • scaly, dry, or rough-to-the-touch skin
  • Gottron’s papules or Gottron’s sign (small bumps over the knuckles, elbows, and knees, often accompanied by raised, scaly breakouts)
  • trouble rising from a seated position
  • persistent fatigue
  • weakness in the neck, hip, back, and shoulder muscles
  • difficulty swallowing
  • voice hoarseness
  • hardened lumps of calcium under the skin
  • muscle pain
  • joint inflammation
  • nail-bed abnormalities
  • unwanted weight loss
  • irregular heartbeat
  • gastrointestinal ulcers

Inclusion-body myositis

Inclusion-body myositis (IBM) occurs more commonly in males than females. Most people who develop this condition are over the age of 50. Experts believe IBM has a strong genetic component.

IBM begins with muscle weakness in the wrists, fingers, and thigh muscles. The muscle weakness is more prominent in smaller muscles and is asymmetrical, with one side of the body becoming weaker than the other.

Other symptoms of IBM may include:

  • difficulty walking due to muscle weakness
  • loss of balance
  • frequent falls
  • trouble rising from a seated position
  • weakened hand grip and diminished hand and finger dexterity (agility)
  • difficulty swallowing
  • muscle pain
  • diminished deep tendon reflexes

Juvenile myositis

Juvenile myositis (JM) occurs in children under the age of 18 years. Girls are twice as likely to develop JM as boys.

Like other forms of myositis, muscle weakness and a skin rash are hallmark features of JM.

Other symptoms of JM may include:

  • persistent fatigue
  • changes in mood or irritability
  • stomachaches
  • motor function difficulties, such as trouble climbing stairs, standing from a seated position, and getting dressed
  • difficulty reaching overhead, as when shampooing or combing hair
  • trouble lifting the head
  • swelling or changes in skin color and texture around the fingernails
  • trouble swallowing
  • hardened lumps of calcium under the skin
  • muscle and joint pain
  • voice hoarseness
  • Gottron’s papules
  • low grade fever

Polymyositis

Polymyositis (PM) begins with muscle weakness in the muscles closest to the trunk and then expands to the limbs. Each case of PM is unique, and people with PM usually receive other debilitating diagnoses, like autoimmune diseases.

Symptoms of PM may include:

  • muscle pain
  • difficulty swallowing
  • falling due to problems with movement and coordination
  • trouble rising from a seated position
  • persistent fatigue
  • chronic dry cough
  • thickening of the skin on the hands
  • difficulty breathing
  • fever
  • changes in weight
  • voice hoarseness

Toxic myositis

Toxic myositis is associated with prescription medications, like statins, and illegal drugs, like cocaine. Although rare, other medications and substances that may trigger myositis include:

  • some immunosuppressants
  • omeprazole (Prilosec)
  • adalimumab (Humira)
  • toluene (a solvent used in paint thinners)

Symptoms of toxic myositis are similar to those of other types of myositis. People who experience this condition typically see improvement once they stop the medication that caused the toxicity.

Myositis is considered an autoimmune condition. That means that the immune system mistakenly attacks the body’s own tissues. The cause of this autoimmune attack has not been established yet, but some experts believe injury and infections may be contributing factors.

Some researchers believe that the onset of myositis is associated with having:

It is not uncommon for people with myositis to receive a misdiagnosis. Myositis is rare, and its primary symptoms, such as muscle weakness and fatigue, may mimic common conditions.

Healthcare professionals may use some of the following strategies to reach an accurate diagnosis:

No specific medications have been approved to treat myositis. However, doctors may use corticosteroids, such as prednisone (Rayos), and immunosuppressant drugs, such as azathioprine (Azasan) and methotrexate (Trexall).

Depending on the type of myositis and symptoms you have, a doctor may try different treatments until you find relief. This may take some trial and error, but symptoms often respond to the right treatment for your needs.

Physical therapy, regular physical activity, daily stretching, and yoga may also help keep muscles strong and flexible and prevent muscle atrophy.

No cure has been found yet for myositis. Some people with severe cases of myositis may require the use of a cane, walker, or wheelchair to move independently. If left untreated, myositis may become more severe and could be fatal in some cases.

Treatment is effective for managing symptoms and preventing complications, and some people may experience partial or complete remission (symptom relief).

Myositis is a rare autoimmune condition that often manifests with symptoms like persistent fatigue, muscle weakness, and a skin rash. It may mimic other conditions, so healthcare professionals may need comprehensive testing to provide an accurate diagnosis.

Treatment for myositis is effective, even though some people may experience long-term debilitating symptoms over time.

You’re not alone

If you or a loved one live with myositis, support is available and can make a difference.

The Myositis Association offers multiple resources, including:

  • support groups
  • healthcare professional finder tools
  • patient assistance programs

For more information, you can visit their website, call 800-821-7356, or use their contact form