Myalgia


Myalgia means "muscle pain" and is a symptom of many diseases and disorders. The most common cause for myalgia is either overuse or over-stretching of a muscle or group of muscles. Myalgia without a traumatic history is often due to viral infections. Longer-term myalgias may be indicative of a metabolic myopathy, some nutritional deficiencies or chronic fatigue syndrome.

Causes

Diseases/Disorders

It is helpful to categorize the causes of myalgia

Infectious

Trichinosis, Typhoid fever, Upper respiratory tract infection, Viral pneumonia, Avian influenza, Common cold, Community-acquired pneumonia, Coccidioidomycosis, Endemic typhus, HIV, Infectious mononucleosis, Legionellosis, Leptospirosis, Lyme disease, Malaria, Marburg virus, Meningitis, Monkeypox, Pharyngitis, Pneumonia, Prostatitis, Psittacosis, Q fever, Rabies, Rift Valley fever, Severe Acute Respiratory Syndrome, Toxic shock syndrome, West Nile, Chikungunya

Autoimmune

Multiple sclerosis, Myositis, Lupus erythematosus, Familial Mediterranean fever, Polyarteritis nodosa, Devic's disease

Metabolic defect

Carnitine palmitoyltransferase II deficiency, Conn's syndrome,

Other

Chronic fatigue syndrome, Hypokalemia, Exercise intolerance, Mastocytosis, Peripheral neuropathy, Eosinophilia myalgia syndrome, Fibromyalgia, Barcoo Fever

Medications

Acrylamide, Darbepoetin, Procainamide, Quinupristin/dalfopristin, Spiriva, Sumatriptan, Vardenafil, Statins, Zetia, Zomig, Boniva

As a Response to Vaccination

A moderate occurrence (25-35%) of myalgia in recipients of tetanus vaccination is identified in the US; it presents in the large muscle groups and at the subcutaneous injection site. When a patient returns with these symptoms (which include fever, poor appetite and lethargy), a clinician who fails to notice the recent tetanus vaccination on the patient's chart is in danger of making a life-threatening misdiagnosis. An item of note is that in heart patients using selective β<sub>1</sub>-blockers such as metoprolol, incidence of myalgia after tetanus vaccination is significantly higher.

Withdrawal Syndromes

Sudden cessation of opioids, barbiturates, benzodiazepines, or alcohol can induce myalgia.

See also