What are the sequelae of subacute thyroiditis?

Subacute thyroiditis is a self-limiting disease, and the vast majority of cases are fully curable. In rare instances, patients may develop hypothyroidism, presenting with symptoms such as fatigue and lethargy.

Subacute thyroiditis—its full name—is a localized thyroid inflammation associated with viral infection. Its primary clinical manifestations include fever and neck pain. It most commonly affects middle-aged women aged 40–50 years. Based on laboratory findings, subacute thyroiditis can be divided into three phases: the thyrotoxic phase, the hypothyroid phase, and the recovery phase—corresponding to the early, middle, and late stages of the disease, respectively.

As a self-limiting condition, subacute thyroiditis spontaneously improves once it reaches a certain stage of progression. Therefore, treatment focuses primarily on symptom relief—particularly fever and pain—using nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, for anti-inflammatory and analgesic effects.