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Hashimoto Thyroiditis

(Autoimmune Thyroiditis)


Glenn D. Braunstein

, MD, Cedars-Sinai Medical Center

Reviewed/Revised Sep 2022
Topic Resources

Hashimoto thyroiditis is chronic, autoimmune inflammation of the thyroid gland.

  • Hashimoto thyroiditis results when antibodies in the body attacks the cells of the thyroid gland—an autoimmune reaction.

  • At first, the thyroid gland may function normally, be underactive (hypothyroidism) or, rarely, overactive (hyperthyroidism)

  • Most people eventually develop hypothyroidism.

  • People with hypothyroidism usually feel tired and cannot tolerate cold.

  • The diagnosis is based on results of a physical examination and blood tests.

  • People with hypothyroidism need to take thyroid hormone for the rest of their life.

Thyroiditis refers to any inflammation of the thyroid gland. Inflammation of the thyroid may be caused by a viral infection or an autoimmune disorder.

The Thyroid

In about 50% of people with Hashimoto thyroiditis, the thyroid is underactive initially. In most of the rest, the thyroid is normal at first (although in a small number of people, the gland initially becomes overactive), after which it usually becomes underactive.

Symptoms of Hashimoto Thyroiditis

Hashimoto thyroiditis often begins with a painless, firm enlargement of the thyroid gland or a feeling of fullness in the neck. The gland usually has a rubbery texture and sometimes feels lumpy. If the thyroid is underactive, people may feel tired and intolerant of cold and have other symptoms of hypothyroidism Symptoms Hypothyroidism is underactivity of the thyroid gland that leads to inadequate production of thyroid hormones and a slowing of vital body functions. Facial expressions become dull, the voice... read more Symptoms . The few who have an overactive thyroid Hyperthyroidism Hyperthyroidism is overactivity of the thyroid gland that leads to high levels of thyroid hormones and speeding up of vital body functions. Graves disease is the most common cause of hyperthyroidism... read more Hyperthyroidism (hyperthyroidism) initially may have palpitations, nervousness, and intolerance of heat.

Diagnosis of Hashimoto Thyroiditis

  • Thyroid function tests (TSH and T4; T3 if hyperthyroidism is suspected)

  • Thyroid antibodies

  • Sometimes a thyroid ultrasound

Doctors do an examination of the thyroid. An ultrasound of the thyroid may be done if the thyroid feels like it has bump (nodules). They measure blood levels of the thyroid hormone thyroxine (T4) (and triiodothyronine (T3) if hyperthyroidism is suspected) and thyroid-stimulating hormone (TSH, a hormone produced by the pituitary gland to stimulate the thyroid gland to produce thyroid hormones) to determine how the gland is functioning (thyroid function tests Thyroid function tests The thyroid is a small gland, measuring about 2 inches (5 centimeters) across, that lies just under the skin below the Adam’s apple in the neck. The two halves (lobes) of the gland are connected... read more ). They also do a blood test for antibodies that can attack the thyroid gland.

Treatment of Hashimoto Thyroiditis

  • Usually thyroid hormone replacement when the patient is clinically hypothyroid and the TSH level is elevated in the blood

  • Avoidance of excess iodine in food or nutritional supplements

Most people eventually develop hypothyroidism and then must take thyroid hormone replacement Treatment Hypothyroidism is underactivity of the thyroid gland that leads to inadequate production of thyroid hormones and a slowing of vital body functions. Facial expressions become dull, the voice... read more Treatment therapy for the rest of their life. Thyroid hormone may also be useful in reducing the size of the enlarged thyroid gland.

People with Hashimoto thyroiditis who are not taking thyroid hormone replacement should avoid high doses of iodine (which can cause hypothyroidism) from natural sources, such as kelp tablets and seaweed; however, iodized salt and iodine-fortified bread are allowed because they contain lower amounts of iodine.

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