Polymyositis is an uncommon chronic muscle disease. The skeletal muscles--those you use for movement--get inflamed and progressively lose strength. Inflammation is the body's normal reaction to injury or infection; it is part of the healing process. However, the inflammatory response sometimes starts and continues without apparent cause. Such is the case with polymyositis. The unprovoked and chronic inflammation in the muscles is destructive rather than helpful. The muscles closest to the trunk of the body (the proximal muscles) are most affected and exhibit the most profound weakness.
Physical Therapy
Physical therapy and exercise are important aspects of treatment for polymyositis. They are used to improve or maintain muscle strength and range of motion in the joints. Heat and ultrasound therapy may be used on the muscles. Orthotic devices to help support weak areas of the body may be prescribed.
Speech and Language Therapy
Polymyositis can cause difficulty swallowing. Speech and language therapy may be advised to evaluate and treat such difficulties.
Corticosteroids
The American College of Rheumatology states that corticosteroid medicines such as prednisone are typically given in high doses after initial diagnosis. Corticosteroids are anti-inflammatory drugs that usually dampen the muscle inflammation of polymyositis resulting in improved strength over 2 to 3 months. Corticosteriods have long-term adverse side effects. Therefore, the dose of this medication is commonly reduced after the initial course of therapy.
Antimetabolite Medications
Antimetabolite medicines interfere with the normal metabolism of active cells. They are commonly used in cancer treatment and to suppress abnormal immune reactions. Azathioprine and methotrexate are two antimetabolite drugs that may be used to inhibit the inflammation of polymyositis.
Immunosuppressant Medications
The American College of Rheumatology advises that severe or treatment-resistant cases of polymyositis may require therapy with strong immunosuppressant medications. Possible options include cyclosporine, mycophenolate, tacrolimus and cyclophosphamide.
Immunoglobulin Therapy
Polymyositis that is resistant to other medicines may respond to intravenous immunoglobulin therapy. This treatment modulates immune system responses, which may lead to clinical improvement.
Antimalarial Medications
In addition to their activity against malaria parasites, some antimalarial drugs such as chloroquine and hydroxychloroquine have anti-inflammatory properties. Hence, these drugs may be used to dampen the abnormal inflammatory response of polymyositis.
