What Is Hashimoto's Thyroiditis?

Thyroiditis is inflammation of the thyroid gland. Chronic lymphocytic thyroiditis (Hashimoto's thyroiditis) is the most common form of thyroid inflammation. Classified as an autoimmune disorder, Hashimoto's thyroiditis occurs when one's own body makes antibodies to attack the thyroid cells. This results in the destruction of functioning thyroid cells and reduces the thyroid's ability to make thyroid hormone.

Hashimoto's thyroiditis is the most common reason people develop hypothyroidism (an underactive thyroid gland). A person with hypothyroidism has to take thyroid hormone pills to keep the level of the hormone normal. The cause of the thyroiditis is not known, but it is most likely a combination of the person's immune system and some environmental factors.


The following are the most common symptoms of Hashimoto's thyroiditis. However, each individual may experience symptoms differently. Symptoms may include:

  • Goiter (benign enlargement of the thyroid gland, causing enlargement of the neck)
  • Symptoms of underactive thyroid gland, which include:
    • Fatigue
    • Muscle weakness
    • Weight gain
    • Sensitivity to cold
    • Depression
    • Hair and skin changes

As the thyroid is attacked by the antibodies, it may initially release greater amounts of thyroid hormone, until the amount of hormone it makes decreases. This is called hashitoxicosis. It does not occur in everyone, but a person may start out with:

  • Sensitivity to heat
  • Rapid heart rate
  • Sweating
  • Weight loss
  • Tremors
  • Anxiety

The symptoms of Hashimoto's thyroiditis may resemble other conditions or medical problems. Always consult your physician for a diagnosis.


In addition to a complete medical history and medical examination, diagnostic procedures for Hashimoto's thyroiditis may include blood tests to detect levels of thyroid hormone and thyroid antibodies.


No treatment is needed for Hashimoto's thyroiditis if your thyroid hormone levels are normal.

However, Hashimoto's thyroiditis usually results in hypothyroidism. If found, hypothyroidism can be treated with thyroid hormone replacement therapy (the administration of thyroid hormone pills). Thyroid hormone replacement therapy should eliminate symptoms of hypothyroidism and usually alleviates the goiter condition, when present. If the goiter does not improve and is causing other problems, such as pain or difficulty swallowing, breathing or speaking, surgery to remove it may be required.