Skip navigation

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

URL of this page: //medlineplus.gov/ency/imagepages/17072.htm

Hypothyroidism

Hypothyroidism

Overview

Hypothyroidism is a decreased activity of the thyroid gland which may affect all body functions. The rate of metabolism slows causing mental and physical sluggishness. The most severe form of hypothyroidism is myxedema, which is a medical emergency.

Review Date 8/19/2026

Updated by: Nowreen Haq, MD, MPH, Specialist in Endocrinology, Obesity Medicine and Internal Medicine. Medical director, ICON Plc and Maryland Endocrinology, Maryland. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.