Inflammatory Myopathies

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Research on muscle diseases such as the inflammatory myopathies is primarily funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), a component of the National Institutes of Health (NIH). 

What are inflammatory myopathies?

The inflammatory myopathies are a group of rare diseases that involve chronic (long-standing) muscle inflammation, muscle weakness, and in some cases, muscle pain. Myopathy is a general term used to describe a number of conditions affecting the muscles. All myopathies can cause muscle weakness. Both children and adults can be affected.

The four main types of chronic, or long-term, inflammatory myopathy are:

  • Polymyositis, which affects skeletal muscles (the type involved in body movement) on both sides of the body
  • Dermatomyositis, which causes progressive muscle weakness
  • Inclusion body myositis, which is characterized by slow, progressive muscle weakness and muscle shrinking and loss of muscle
  • Necrotizing autoimmune myopathy, which involves muscle weakness in the upper and lower body

The majority of the inflammatory myopathies are considered to be autoimmune disorders, in which the body's immune response system that normally defends against infection and disease attacks its own muscle fibers, blood vessels, connective tissue, organs, or joints.

Learn About Clinical Trials
Clinical trials are studies that allow us to learn more about disorders and improve care. They can help connect patients with new and upcoming treatment options.

How can I or my loved one help improve care for people with inflammatory myopathy?

Consider participating in a clinical trial so clinicians and scientists can learn more about the inflammatory myopathies and related disorders.  Clinical research uses human volunteers to help researchers learn more about a disorder and perhaps find better ways to safely detect, treat, or prevent disease.

All types of volunteers are needed—those who are healthy or may have an illness or disease—of all different ages, sexes, races, and ethnicities to ensure that study results apply to as many people as possible, and that treatments will be safe and effective for everyone who will use them.

For information about participating in clinical research visit NIH Clinical Research Trials and You. Learn about clinical trials currently looking for people with myopathy at

Where can I find more information about inflammatory myopathies?

The following organizations offer resources that help individuals, families, friends, and caregivers of people with myopathy and muscle diseases:

Autoimmune Association
Phone: 586-776-3900

Myositis Association
Phone: 800-821-7356

Muscular Dystrophy Association
Phone: 800-572-1717

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