Myositis is an inflammation or swelling of the muscles. It is most often caused by injury, infection, medicines, or an autoimmune disorder.
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Taber's Cyclopedic Medical Dictionary. 24th ed. Philadelphia, PA: F.A. Davis Company; 2021. Myositis. www.tabers.com/tabersonline/view/Tabers-Dictionary/729759/all/myositis. Accessed June 12, 2023.
Review Date 4/27/2023
Updated by: Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.