Treating Hashimoto's Thyroiditis With Normal TSH

New Research Says It Can Help

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Are you wondering if your Hashimoto's thyroiditis should be treated when your other thyroid blood test levels are normal and within the reference range?  It's a question many thyroid patients find themselves facing. 

You may find yourself in a situation that affects many other thyroid patients: You have Hashimoto's disease, but your thyroid stimulating hormone (TSH), free T4 and free T3 blood test levels fall within the reference range.

Still, you are experiencing a range of hypothyroidism symptoms, including fatigue, weight gain, brain fog, depression, swelling, joint and muscle aches and pains, hair loss, and other problems. The reality is that your symptoms may be the direct result of your underlying autoimmune thyroid disease. But even if you want treatment, will you be able to get it? 

First, it's important to know that many endocrinologists believe that having Hashimoto's disease, as shown by elevated thyroid peroxidase antibodies (TPOAb) or thyroid biopsy results, is not enough reason to treat you, as long as your thyroid stimulating hormone (TSH) test result puts you within the normal reference range. 

It's a controversial issue, however. Some conventional physicians believe that Hashimoto's disease should only be treated if your TSH test result shows overt hypothyroidism, for example, a TSH over 10.0. Some believe that you should be treated if you have "subclinical hypothyroidism," a TSH that is above the reference range but not above 10.0.

Some doctors believe that no treatment is warranted and that a "watch and wait" approach should be taken until your TSH level goes above the reference range, or even above 10.0.

Should Hashimoto's Be Treated When TSH is Normal?

The question of whether Hashimoto's should be treated when TSH is normal is the key question.

Many conventional physicians believe there is no benefit to treatment, but there are a number of research studies that show that in those patients with Hashimoto's/elevated TPOAb, treatment with thyroid hormone replacement medication can actually accomplish three important objectives in a significant percentage of patients:

In one study of patients who had Hashimoto's disease, but whose TSH thyroid levels were normal (referred to as "euthyroid"), a double-blind study was conducted. One study group of patients received levothyroxine (also known as LT4) treatment, and the other group of patients did not receive any thyroid treatment.

After 15 months, the treated group showed major changes in their thyroid test levels, including:

  • significantly increased free thyroxine (free T4) levels
  • significantly decreased TSH levels
  • a reduction in both anti-thyroglobulin antibody (TgAb) and TPOAb

In the group that received the thyroid treatment, the actual size of the thyroid gland decreased significantly in the treated group, while those who did not receive treatment had an increase in the size of their thyroid.

Despite these findings, the researchers were still equivocal in their findings, concluding that: 

Although levothyroxine treatment is mandatory in hypothyroid autoimmune thyroiditis patients, the LT4 treatment which is shown to inhibit autoimmune process in animal models is still controversial in euthyroid Hashimoto's disease patients where the disease has not destroyed the thyroid gland enough to cause hypothyroidism.

They found, however, that levothyroxine treatment that kept the TSH level at low-normal levels appeared to be effective in two ways:

  • The treatment decreased antibody levels
  • The treatment decreased the goiter size 

    Both reduced antibodies and reducing the size of the thyroid gland are both markers suggesting that the treatment could ultimately slow or prevent you from progressing to full, overt hypothyroidism. 

    A Word from Verywell 

    It's important to recognize that this is a controversial issue, and doctors view the issue in different ways. If you have Hashimoto's thyroiditis, as evidenced by elevated TPOAb, and are symptomatic, you may be denied treatment by a conventional doctor or endocrinologist because your TSH test results are in the reference range If you find yourself in this situation, consider consulting with an integrative physician who specializes in autoimmune disease, thyroid disease, and hormone balance. These physicians are more likely to consider the bigger picture, and are more willing to treat "subclinical" or autoimmune hypothyroidism. They are also more knowledgeable about approaches that can help address your elevated antibodies and autoimmunity. 


    Aksoy DY, et al. "Effects of prophylactic thyroid hormone replacement in euthyroid Hashimoto's thyroiditis." Endocr J. 2005 Jun;52(3):337-43. PMID: 16006728 

    Duygu Yazgan Aksoy, et. al. "Effects of Prophylactic Thyroid Hormone Replacement in Euthyroid Hashimoto's Thyroiditis" Endocr J (Japan) Vol. 52: 337-343, (2005).

    Padberg S, et al. "One-year prophylactic treatment of euthyroid Hashimoto's thyroiditis patients with levothyroxine: is there a benefit?" Thyroid. 2001 Mar;11(3):249-55.

    Thyroid, 2001 Mar;11(3):249-55, "One-year prophylactic treatment of euthyroid Hashimoto's thyroiditis patients with levothyroxine: is there a benefit?"