Polymyositis (PM) is found mostly in people over the age of 20 and affects more women than men. Muscle weakness usually happens over days, weeks, or months. The weakness begins with muscles closest to and within the trunk of the body, such as the muscles of the neck, hips, back, and shoulders. Some patients also feel weakness in muscles farther from the trunk, such as hands and fingers. Some PM patients may also experience muscle pain, breathing problems, and trouble swallowing.

Signs and symptoms:

  • Marked weakness in the muscles closest to the center of the body, like the forearms, thighs, hips, shoulders, neck, and back
  • Sometimes, weakness in the fingers and toes
  • Falling and difficulty getting up from a fall
  • Chronic dry cough
  • Difficulty swallowing (dysphagia)