ICD-10 Code B33.0 – Epidemic myalgia (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B33.0 – Epidemic myalgia
What it is
Use this code for epidemic myalgia, an acute viral illness marked by sudden muscle pain. It is commonly associated with enteroviral infection, especially Coxsackie virus.
Clinical signs
Typical findings include abrupt onset of severe muscle pain, often in the chest or upper abdomen, with possible fever and malaise. Clinical features vary; refer to documentation.
When to use this code
Assign B33.0 when the provider documents epidemic myalgia or Bornholm disease. Use it when the record identifies a viral myalgia syndrome rather than a nonspecific muscle pain complaint. If the note only says myalgia without an epidemic or viral cause, check documentation.
Do not use for
Do not use this code for routine muscle pain, trauma-related pain, or myositis without documentation of epidemic myalgia. Also avoid it when the diagnosis is uncertain or not specifically stated.
Coding tip
Code only when the provider clearly links the illness to epidemic myalgia; otherwise, query for clarification.