Hashimoto's thyroiditis is a chronic (ongoing) condition where the body's immune system attacks the thyroid, a gland in the neck that makes thyroid hormone.

More to Know

The thyroid hormone helps the body handle many chemical reactions, controls how the body converts food into energy, and helps direct growth and sexual development.

In someone with Hashimoto's, often the thyroid must work harder to make thyroid hormone. This, and the inflammation that occurs in the gland, can cause the thyroid to swell, resulting in a goiter.

In some cases, the thyroid can't produce enough thyroid hormone. This is called hypothyroidism. Symptoms of hypothyroidism may include sluggishness, dry skin, feeling cold, constipation, facial puffiness, weight gain, and slowing of growth and sexual development.

In rare cases, the immune system of someone with Hashimoto's thyroiditis can cause inflammation in the brain and nervous system. Symptoms can include strange behavior, confusion, muscle twitching, and seizures.

Keep in Mind

Hashimoto's thyroiditis is usually diagnosed by blood tests measuring the levels of thyroid hormone and the presence of antibodies. Hashimoto's is a chronic disorder, although the size of the thyroid and its ability to make thyroid hormone can increase or decrease over months and years.

Treatment depends on symptoms and the results of lab tests. Hypothyroidism and goiters are usually treated with synthetic thyroid hormone taken in pill form. The treatment and dose of medication is guided by regular periodic blood tests and doctor visits. Surgery is sometimes done to treat goiters, especially if the thyroid becomes large enough to cause problems with swallowing.

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