From the Guidelines
Hashimoto's thyroiditis should be treated when it causes hypothyroidism, which is typically indicated by elevated thyroid-stimulating hormone (TSH) levels above the normal range, often with low free T4 levels. The decision to treat is based on the presence of hypothyroidism rather than the presence of Hashimoto's thyroiditis itself. According to the most recent and highest quality study 1, for patients without risk factors, full replacement can be estimated using ideal body weight for a dose of approximately 1.6 mcg/kg/d of levothyroxine.
Key Considerations for Treatment
- The standard treatment is levothyroxine (synthetic T4), taken on an empty stomach 30-60 minutes before breakfast or 3-4 hours after the last meal of the day.
- Medication should be taken separately from calcium, iron supplements, and certain foods that can interfere with absorption.
- Dosage adjustments are made based on TSH levels measured 6-8 weeks after starting therapy, with the goal of achieving a TSH within the normal range.
- Importantly, Hashimoto's without hypothyroidism (normal TSH) generally doesn't require thyroid hormone replacement.
- Treatment is lifelong, and patients need regular monitoring, usually with TSH checks every 6-12 months once stable.
Special Considerations
- Elevated TSH can be seen in the recovery phase of thyroiditis. In asymptomatic patients with FT4 that remains in the reference range, it is an option to monitor before treating to determine whether there is recovery to normal within 3-4 weeks, as suggested by 1.
- Development of a low TSH on therapy suggests overtreatment or recovery of thyroid function, and dose should be reduced or discontinued with close follow-up.
- For those older than age 70 years and/or frail patients with multiple comorbidities, consider titrating up from a lower starting dose of 25-50 mcg of levothyroxine, as recommended by 1.
Monitoring and Adjustment
- Regular monitoring of TSH levels is crucial to adjust the dosage of levothyroxine and ensure that the patient's thyroid hormone levels remain within the normal range.
- The goal of treatment is to alleviate symptoms of hypothyroidism, such as fatigue, cold intolerance, weight gain, and cognitive issues, and to prevent long-term complications associated with untreated hypothyroidism.
From the FDA Drug Label
As replacement or supplemental therapy in patients with hypothyroidism of any etiology, except transient hypothyroidism during the recovery phase of subacute thyroiditis As pituitary thyroid-stimulating hormone (TSH) suppressants, in the treatment or prevention of various types of euthyroid goiters, including thyroid nodules, subacute or chronic lymphocytic thyroiditis (Hashimoto's) and multinodular goiter
Treatment of Hashimoto's should be considered when there is evidence of hypothyroidism or a euthyroid goiter.
- Replacement or supplemental therapy may be indicated in patients with hypothyroidism due to Hashimoto's thyroiditis.
- TSH suppressants may be used in the treatment or prevention of euthyroid goiters associated with Hashimoto's. 2
From the Research
Treatment of Hashimoto's Thyroiditis
Hashimoto's thyroiditis is a common autoimmune disorder that affects the thyroid gland, leading to hypothyroidism. The treatment of Hashimoto's thyroiditis depends on the stage and severity of the disease.
- Hypothyroidism: Treatment with thyroid hormone replacement therapy, typically levothyroxine (LT4), is indicated for patients with overt hypothyroidism 3, 4. The dose of LT4 is based on the degree of preserved thyroid functionality and lean body mass, and usually ranges from 1.4 to 1.8 mcg/kg/day 3.
- Euthyroidism: Patients with euthyroid Hashimoto's thyroiditis may not require treatment, but regular monitoring of thyroid function is recommended to assess for progression to hypothyroidism 3, 4. However, some studies suggest that prophylactic thyroid hormone replacement therapy may be beneficial in reducing the incidence and alleviating symptoms of the disease, even in euthyroid patients 5, 6.
- Thyrotoxicosis: The management of Hashitoxicosis is based on symptoms control, usually with β-blockers 3.
- Pregnancy: Levothyroxine is the preferred treatment for hypothyroidism in pregnancy, as triiodothyronine (T3) does not sufficiently cross the fetal blood-brain barrier 3.
Special Considerations
- Papillary thyroid cancer and thyroid lymphoma: Hashimoto's thyroiditis is associated with an increased risk of papillary thyroid cancer and thyroid lymphoma, and regular surveillance is recommended 3.
- Severe prolonged hypothyroidism: Treatment with levothyroxine can rapidly restore neurocognitive function and normalize laboratory tests, even in cases of severe prolonged hypothyroidism 7.