Polymyositis is a rare inflammatory disease that results in muscle weakness affecting both sides of the body. This condition can make it difficult to climb stairs, stand up from a seated position, lift objects, or reach for things located at a height.

Polymyositis typically affects individuals in their 30s, 40s, or 50s, and is more commonly seen in women than men. The onset of signs and symptoms is usually gradual, occurring over a period of several weeks or months.

While there is currently no known cure for polymyositis, it is possible to improve muscle strength and function through the use of medication and physical therapy.


Below are a few signs and symptoms of polymyositis. These signs may appear and disappear:

  • Weakness of the muscles: Being the most typical symptom is this, the muscles involved are often those closest to the body’s trunk, and weakening typically develops gradually over a period of 3 to 6 months, with rare exceptions where symptoms appear suddenly.
  • Difficulty getting up from chairs, climbing stairs, or lifting objects: Some individuals find it difficult to stand up after lying down.
  • Muscle pain: Muscles may occasionally ache and feel painful to the touch.
  • Fatigue.
  • Fever.
  • Weight loss.
  • Swallowing problem.
  • Breathing difficulty brought on by heart and lung involvement.
  • Red patches or violet rash surrounding the eyes: Some individuals also have red rashes on their neck and upper chest, as well as spotty, red skin over their fingers, elbows, and knees.

If you experience unexplained muscle weakness, see a doctor.


Although the cause of polymyositis is not yet fully understood, the condition shares many similarities with autoimmune disorders, in which the immune system mistakenly attacks the body’s own tissues and organs.

Risk factors

Polymyositis tends to progress gradually over time and is rarely seen in individuals under the age of 18. Women are more frequently affected by the condition than men. If you have lupus, rheumatoid arthritis, scleroderma, or Sjogren’s syndrome, your risk of developing polymyositis is increased.