What Are Some Symptoms of Low Thyroid Function?

Symptoms of hypothyroidism or low thyroid hormone production include coarse hair, dry skin, slow body movements, inability to tolerate cold, constipation, and feeling sluggish or weak, explains WebMD. Rarer symptoms include an enlarged thyroid gland, weight gain, swelling in the hands and feet, and muscle aches.

The symptoms of hypothyroidism often develop over a period of months or years, explains WebMD. The severity of a patient's symptoms depend on how long he has had hypothyroidism, his age and the extent of the hormone deficiency. Patients with mild hypothyroidism may go undiagnosed for years, only experiencing vague symptoms such as memory problems, dry skin and fatigue. In older patients, these symptoms often lead to a misdiagnosis of dementia or Alzheimer's disease.

The thyroid gland is located in the neck, and it produces hormones that affect the entire body, explains WebMD. There are several possible reasons why the thyroid gland may not make enough hormones. A condition called Hashimoto's thyroiditis causes the immune system to attack the thyroid gland, which reduces hormone production. Radiation exposure can reduce thyroid hormone secretion, as can certain viral infections and some medications. Hypothyroidism is diagnosed with a simple blood test to measure the levels of thyroid hormone in the bloodstream. Most cases are treated with oral medications such as levothyroxine.