Myositis
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
Myositis means inflammation of the muscles that you use to move your body. An injury, infection, or autoimmune disease can cause it. Two specific kinds are polymyositis and dermatomyositis. Polymyositis causes muscle weakness, usually in the muscles closest to the trunk of your body. Dermatomyositis causes muscle weakness, plus a skin rash.
Other symptoms of myositis may include:
- Fatigue after walking or standing
- Tripping or falling
- Trouble swallowing or breathing
Doctors may use a physical exam, lab tests, imaging tests and a muscle biopsy to diagnose myositis. There is no cure for these diseases, but you can treat the symptoms. Polymyositis and dermatomyositis are first treated with high doses of a corticosteroid. Other options include medications, physical therapy, exercise, heat therapy, assistive devices, and rest.
NIH: National Institute of Neurological Disorders and Stroke
Symptoms, tests and care options
Further reading selected by MedlinePlus. Links open the original organizations’ websites.
- ANA (Antinuclear Antibody) Test · National Library of Medicine
- Dermatomyositis: Diagnosis · Muscular Dystrophy Association
- Dermatomyositis: Signs and Symptoms · Muscular Dystrophy Association
- Dermatomysitis: Medical Management · Muscular Dystrophy Association
- Electromyography (EMG) and Nerve Conduction Studies · National Library of Medicine
- Inflammatory Myopathies (Signs/Symptoms and Common Treatments) · American College of Rheumatology
- Polymyositis (PM): Medical Management · Muscular Dystrophy Association
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