Treatment of Subacute Thyroiditis

Clinical Presentation and Diagnosis

Laboratory evaluation should include TSH, free T4, and inflammatory markers; T3 can be helpful in highly symptomatic patients with minimal FT4 elevations 2

Beta-blockers (e.g., atenolol or propranolol) for symptomatic relief of adrenergic symptoms such as palpitations, tremors, and fever 1, 2
Close monitoring of thyroid function every 2-3 weeks to detect transition to hypothyroidism 2

Beta-blockers for symptomatic relief during the thyrotoxic phase 1, 2
Hydration and supportive care 2
For persistent thyrotoxicosis (>6 weeks), refer to endocrinology for additional workup 2
Treat transition to elevated TSH and low FT4 as primary hypothyroidism with levothyroxine 1, 2
For patients without risk factors (<70 years old, not frail, without cardiac disease), full replacement can be estimated using ideal body weight (approximately 1.6 mcg/kg/day) 1
For older patients (>70 years) or those with comorbidities, start with lower doses (25-50 mcg) 1

Thyroiditis is self-limited, with the initial hyperthyroidism generally resolving in weeks with supportive care 2

Monitor thyroid function every 2-3 weeks during the initial phase 2, 4
For persistent thyrotoxicosis (>6 weeks), endocrinology consultation is recommended 2
In asymptomatic patients with elevated TSH but FT4 within reference range during recovery phase, consider monitoring before treating to determine if there is recovery to normal within 3-4 weeks 1
Development of low TSH on therapy suggests overtreatment or recovery of thyroid function; dose should be reduced or discontinued with close follow-up 1