Myositis is an inflammatory condition that affects the muscles, leading to weakness and discomfort. It can occur due to various reasons, including autoimmune diseases, infections, or certain medications. The inflammation can make it difficult for individuals to perform everyday activities, such as climbing stairs or lifting objects. There are different types of myositis, including polymyositis and dermatomyositis, each with unique symptoms and causes. Diagnosis typically involves blood tests, imaging studies, and sometimes a muscle biopsy. Treatment often includes medications to reduce inflammation and physical therapy to improve muscle strength and function.