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 Medical Dictionary Online. Myositis. www.tabers.com/tabersonline/view/Tabers-Dictionary/729759/all/myositis. Accessed April 29, 2021.
Review Date 5/3/2021
Updated by: Linda J. Vorvick, MD, Clinical Associate Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.