A condition in which the thyroid gland doesn't make enough thyroid hormones.

Hypothyroidism can happen due to various health issues that affect the thyroid. The thyroid is a small gland at the base of the neck. It makes hormones that control the process by which the body turns food and drink into energy. Hypothyroidism slows this process over time. Another name for the condition is underactive thyroid.

Hypothyroid symptoms tend to show up slowly, often over years. They can include tiredness, weight gain, constipation, thinning hair and dry skin. The face may look puffy. The voice might sound hoarse. Muscles may feel weak, tender, achy or stiff. Menstrual cycles may be heavier than usual or less frequent.

Hypothyroidism treatment most often includes medicine. A lab-made version of thyroid hormone is taken daily by mouth. It raises hormone levels to a healthy range and stops hypothyroidism symptoms. Treatment likely will be lifelong. The amount of medicine taken and how often it's taken may change over time.