The most common causes of muscle pain are tension, stress, overuse and minor injuries. This type of pain is usually localized, affecting just a few muscles or a small part of your body.

Systemic muscle pain — pain throughout your whole body — is more often the result of an infection, an illness or a side effect of a medication.

Common causes of muscle pain include:

Chronic exertional compartment syndrome
Chronic fatigue syndrome
Claudication
Dermatomyositis
Dystonia
Fibromyalgia
Hypothyroidism (underactive thyroid)
Influenza (flu)
Lupus
Lyme disease
Medications, especially the cholesterol medications known as statins
Muscle cramp
Myofascial pain syndrome
Polymyalgia rheumatica
Polymyositis
Repetitive strain injuries
Rheumatoid arthritis
Rocky Mountain spotted fever