Hashimoto Thyroiditis

(Hashimoto Disease)

How to say it: Hash-E-Mo-To Thi-Royd-I-Tiss


The thyroid gland is shaped like a butterfly and located in the front of the neck. It makes hormones that control metabolism. Hashimoto thyroiditis (HT) is caused by a problem with the immune system.


The body makes antibodies to fight germs. In HT, the body makes antibodies that attack the thyroid. This leads to inflammation and damage of the thyroid. It is not clear why the body begins to make this type of antibody.

Risk Factors

HT is more common in women than in men. It often appears between the ages of 30 and 50.

Factors that may increase the risk of HT include:


Symptoms may not be present during early stages of HT. When symptoms are present, they begin with enlargement of the thyroid gland. The front of the neck may look swollen. This enlargement of the gland is called a goiter.

Other symptoms may include:

  • Underactive thyroid (hypothyroidism) symptoms:
    • Fatigue
    • Constipation
    • Weight gain
    • Difficulty tolerating cold temperatures
    • Facial puffiness
    • Dry skin
    • Hair loss
    • A hoarse throat
  • Overactive thyroid (hyperthyroidism) symptoms:
    • Rapid heart beat
    • Weight loss
    • Diarrhea
    • Tremors
    • Difficulty sleeping


You will be asked about your symptoms and medical history. A physical exam will be done. Your body’s fluids will be tested. This can be done with:

  • Blood tests to check for anti-thyroid antibodies and thyroid function
  • Biopsy and testing of thyroid nodules that concern your doctor

Imaging tests may be done if you have a nodule or goiter. These may include:


Not everybody with HT will need treatment. Regular blood tests and symptom checks will be done to look for any changes. When treatment is needed, options include:


Medicine can be used to replace the hormone that your thyroid cannot make. It can take some time to find the right dose for you.


Thyroid tissue may grow to try to meet hormone needs. This can lead to a goiter. Surgery may be needed to remove the extra tissue or the entire thyroid.


There is no known way to prevent HT. It is caused by a problem with the immune system.


American Thyroid Association

National Institute of Diabetes and Digestive and Kidney Diseases


Health Canada

Thyroid Foundation of Canada


Hashimoto thyroiditis. EBSCO DynaMed website. Available at:http://www.dynamed.com/topics/dmp~AN~T113943/Hashimoto-thyroiditis. Accessed March 17, 2020.

Hashimoto’s disease. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: https://www.niddk.nih.gov/health-information/endocrine-diseases/hashimotos-disease. Accessed March 17, 2020.

Hashimoto’s thyroiditis (lymphocytic thyroiditis). American Thyroid Association website. Available at: https://www.thyroid.org/hashimotos-thyroiditis/. Accessed March 17, 2020.

Hashimoto’s thyroiditis overview. EndocrineWeb website. Available at: https://www.endocrineweb.com/conditions/hashimotos-thyroiditis/hashimotos-thyroiditis-overview. Accessed March 17, 2020.

Last reviewed March 2020 by EBSCO Medical Review Board Daniel A. Ostrovsky, MD  Last Updated: 3/18/2020