Myositis: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Myositis?
A rheumatologist, a doctor who treats autoimmune and muscle diseases, usually treats myositis. Myositis means inflammation of the muscles that you use to move your body. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is myositis?
An injury, infection, or autoimmune disease can cause myositis. Two kinds are polymyositis and dermatomyositis.
Polymyositis causes muscle weakness, usually in the muscles closest to the trunk of the body. Dermatomyositis causes muscle weakness plus a skin rash.
Inflammatory myopathies are muscle diseases. Inflammation causes them. They are rare. The most common are dermatomyositis and polymyositis. People of all ages and races may get them.
Symptoms
The most common sign of inflammatory myopathies is weakness in the large muscles of the shoulders, neck or hips. Inflammatory myopathies may cause problems like these.
- Weakness with climbing stairs, getting out of a seat or lifting objects above the head.
- Choking while eating, shortness of breath or a cough.
- A rash on the knuckles, eyelids, knees or elbows.
You may also feel tired after walking or standing, trip or fall, or have trouble swallowing or breathing.
Dermatomyositis can also cause rashes.
Causes and who gets it
An injury, infection, or autoimmune disease can cause myositis. In an autoimmune disease, the immune system attacks the body's own tissue. Here, it attacks the muscles.
With inflammatory myopathies, children are usually diagnosed between ages 5 and 10. Adults are usually diagnosed between ages 40 and 50. Women get them twice as often as men.
How doctors diagnose it
A strength exam comes first. Doctors may also use lab tests, imaging tests and a muscle biopsy. A biopsy tests a small piece of muscle.
A specialist may also order these tests.
- Blood tests.
- An EMG test, which measures electrical activity in the muscles.
- Magnetic resonance imaging (MRI), which looks for muscle damage.
Inflammatory myopathies may be linked to cancer, so tests to rule out cancer may be needed.
Treatment
There is no cure for polymyositis and dermatomyositis, but you can treat the symptoms. Doctors first treat them with high doses of a corticosteroid, a medicine that lowers swelling.
Other medicines, such as methotrexate or azathioprine, may be added. They help control the disease over time. They also help avoid the long-term side effects of corticosteroids. Some people with severe disease may need intravenous immunoglobulin (IVIG), a treatment given through a vein.
The FDA has approved a tablet called Lisraya (brepocitinib) for dermatomyositis in adults. Lisraya carries a boxed warning for serious infections and a higher risk of death from any cause. The warning also covers cancers, serious heart and blood vessel problems, and blood clots.
Other options are physical therapy, exercise, heat, assistive devices and rest. People with dermatomyositis should use sun protection so rashes do not get worse. If you have trouble swallowing, eat soft foods or puree solid foods in a blender.
Follow your doctor's instructions about every medicine.
When to see a doctor
See a doctor if you have muscle weakness, tripping or falling, or trouble swallowing.
Call 911 or go to the emergency room if you have trouble breathing, choking, chest pain lasting two minutes or more, or fainting.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. A direct primary care doctor can review your symptoms and follow your overall health at regular visits. They can refer you to a specialist.
Common questions
Is myositis an autoimmune disease?
Often, yes. An autoimmune disease can cause myositis, but an injury or infection can also cause it.
Can myositis be cured?
For polymyositis and dermatomyositis, no. There is no cure, but you can treat the symptoms. Doctors first treat these diseases with high doses of a corticosteroid.
What is the difference between polymyositis and dermatomyositis?
Dermatomyositis causes a skin rash along with muscle weakness. Polymyositis causes muscle weakness.
Can children get myositis?
Yes, children can get myositis.
Sources
- MedlinePlus - Myositis
- American College of Rheumatology - Inflammatory Myopathies
- FDA - FDA Approves First Oral Drug Indicated to Treat Dermatomyositis in Adults
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
