Menu Healthy Lifestyle Diseases & Conditions First Aid Symptoms Tests & Procedures Videos Definitions FAQs Autoimmune thyroiditisUpdated: 2019-10-03OverviewAutoimmune thyroiditis is a condition in which the immune system attacks the thyroid, a small gland at the base of the neck. The thyroid produces hormones that coordinate many of the body's activities.SymptomsSymptoms may include fatigue, pale and dry skin, and weight gain.TreatmentsHormone replacement medications are an effective treatment. © 1998-2022 Mayo Foundation for Medical Education and Research(MFMER). All rights reserved. Terms of Use