Dermatomyositis: Causes, Symptoms, and Treatment
Medically reviewed by Sumiran Racherla, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Dermatomyositis?
A rheumatologist, a doctor who treats immune system and connective tissue diseases, usually leads care for dermatomyositis. A dermatologist, a skin doctor, often helps with the rash. 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 dermatomyositis?
Dermatomyositis is a rare disease that causes muscle inflammation, which is swelling and irritation, along with a skin rash. It is an autoimmune disease. That means the immune system attacks the body's own muscles and skin.
It belongs to a group of diseases called inflammatory myopathies. These cause long-lasting muscle inflammation and weakness.
Symptoms
Muscle weakness can come on slowly or suddenly. Common signs include:
- Muscle weakness, stiffness, or soreness.
- Trouble raising your arms over your head, getting up from a sitting position, and climbing stairs.
- A purple color to the upper eyelids.
- A purple-red skin rash on the face, knuckles, neck, shoulders, upper chest, and back.
- Trouble swallowing.
In up to 40% of people, skin changes may be the only sign at first.
Shortness of breath or a cough can mean the lungs are involved.
Causes and who gets it
The exact cause is unknown. Experts think genes, the immune system, and the environment may all play a part.
It may also occur in people who have cancer in the abdomen, lung, or other parts of the body.
Anyone can develop it. It most often occurs in children age 5 to 15 and adults age 40 to 60. It affects women more often than men.
How doctors diagnose it
Your doctor will do a physical exam. Tests may include:
- Blood tests for muscle enzymes, which are proteins that rise when muscles are inflamed.
- Blood tests for autoimmune diseases and for myositis antibodies.
- Electromyography (EMG), a test that records the electrical activity of muscles.
- An MRI scan, which makes detailed pictures of the muscles.
- A muscle biopsy or skin biopsy, where a small sample is removed and looked at under a microscope.
- A chest X-ray, a chest CT scan, and lung function tests to check the lungs.
- A swallowing study and cancer screening tests.
Treatment
Treatment depends on the symptoms and differs from person to person.
The first treatment is usually a corticosteroid medicine, also called a steroid. Doctors lower the amount slowly as muscle strength improves. Never stop steroids suddenly unless your doctor is supervising you.
Medicines that calm the immune system, such as azathioprine, methotrexate, or mycophenolate, may be used as well. They can raise the risk of infections. If the disease stays active, doctors may try intravenous gamma globulin, which is given through a vein, or biologic medicines.
The FDA has approved Lisraya (brepocitinib), a once-daily tablet, for adults with dermatomyositis. It is the first oral drug approved for this use. It carries a boxed warning, a serious safety warning, for serious infections, a higher risk of death from any cause, cancers, serious heart and blood vessel problems, and blood clots.
Skin care includes avoiding the sun and using sunscreen. If a tumor is causing the condition, the weakness and rash may get better when the tumor is removed.
Severe illness can lead to disability and sometimes death. Regular follow-up with a doctor is important.
When to see a doctor
Contact your provider if you have muscle weakness or other symptoms of dermatomyositis, such as trouble swallowing.
Call 911 or go to the emergency room if you have severe trouble breathing, chest pain, fainting, or choking. In rare cases, weak chest muscles can make breathing hard, and this can become life threatening without prompt treatment.
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. Either can look at new muscle weakness or a rash, order first blood tests, and refer you to a rheumatologist.
Common questions
Is dermatomyositis an autoimmune disease?
Yes, it is thought to be. In an autoimmune disease, the immune system attacks the body's own tissue. In dermatomyositis, the immune system attacks the muscles and skin.
Can dermatomyositis affect the lungs?
Yes. It can cause lung disease, which may lead to trouble breathing and a cough. Doctors may check the lungs with a chest X-ray, a chest CT scan, and lung function tests.
Is dermatomyositis linked to cancer?
Yes, in some people. It may occur in people who have cancer, and this is seen more often in people over about 40 to 50. The childhood form is rarely linked to cancer.
Sources
- MedlinePlus - Dermatomyositis
- National Organization for Rare Disorders - Dermatomyositis
- U.S. Food and Drug Administration - 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.
