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Quick Facts

Hashimoto Thyroiditis


The Manual's Editorial Staff

Last full review/revision Jul 2020| Content last modified Jul 2020
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Your thyroid is a gland below the Adam’s apple in your neck.

Your thyroid releases thyroid hormones. The hormones control how fast your body’s chemical functions work (metabolic rate). Almost every cell in your body needs thyroid hormones. Among many other things, thyroid hormones help control:

  • How fast you burn calories

  • How fast your heart beats

  • Your body temperature

Locating the Thyroid Gland

Locating the Thyroid Gland

What is Hashimoto thyroiditis?

In Hashimoto thyroiditis, your body's immune system mistakenly attacks your thyroid. This type of disease is called an autoimmune disease.

  • Your thyroid gland gets bigger and stops making enough hormones (hypothyroidism)

  • People with hypothyroidism usually feel tired and get cold easily

  • If you get hypothyroidism, you will need to take thyroid hormone pills for the rest of your life

What causes Hashimoto thyroiditis?

Doctors don't know why your body's immune system attacks your thyroid gland. It's more common in middle-aged women and tends to run in families. Sometimes it happens in people with other autoimmune problems such as rheumatoid arthritis.

What are the symptoms of Hashimoto thyroiditis?

Early on, you may have no symptoms, or you may notice:

  • Painless, firm, slight swelling of your thyroid gland

  • Feeling of fullness in your neck

If your thyroid stops making enough hormones, you get symptoms of hypothyroidism, such as:

  • Feeling tired

  • Getting cold easily

  • Puffy eyes and face, droopy eyelids

  • Thin, rough, dry hair

How can doctors tell if I have Hashimoto thyroiditis?

Doctors will do:

Blood tests may also check for antibodies to your thyroid. Doctors will usually also do an ultrasound of your thyroid.

How do doctors treat Hashimoto thyroiditis?

There's no treatment for Hashimoto thyroiditis itself.

If you have hypothyroidism, doctors will give you:

  • Thyroid hormone pills

Once treatment is started, doctors will gradually adjust the dose of hormone pills based on blood tests.

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