Hypothyroidism is a condition in which the thyroid is underactive, and the gland doesn’t produce enough hormones.

The thyroid is a small, butterfly-shaped gland located at the front of the neck below the Adam’s apple. The thyroid produces the hormones triiodothyronine (T3) and thyroxine (T4) and affects metabolism, body temperature and heart rate.


Signs of hypothyroidism include:

  • Constipation
  • Weight gain
  • Fatigue
  • Puffy face
  • Increased sensitivity to cold
  • Hoarseness
  • Dry skin
  • Muscle weakness
  • Thinning hair
  • Elevated blood cholesterol level
  • Slowed heart rate
  • Depression
  • Muscle aches, tenderness and stiffness
  • Impaired memory
  • Unusually heavy or irregular menstrual periods
  • Pain, swelling or stiffness in the joints
  • Enlarged thyroid gland

Newborns with hypothyroidism may exhibit the following symptoms:

  • Hoarse crying
  • A large, protruding tongue
  • An umbilical hernia
  • Yellowing of the skin and whites of the eyes (jaundice)
  • Constipation
  • Excessive sleepiness
  • Poor muscle tone

Teens with hypothyroidism may have the following symptoms:

  • Delayed puberty
  • Poor mental development
  • Poor growth
  • Delayed development of permanent teeth

If left untreated, hypothyroidism may lead to:

  • Goiter
  • Heart problems
  • Myxedema
  • Mental health problems
  • Peripheral neuropathy
  • Infertility
  • Birth defects


Hypothyroidism may be caused by the following factors:

  • Autoimmune disorders, such as Hashimoto’s thyroiditis, may produce antibodies that attack tissues such as the thyroid gland.
  • Thyroid surgery may diminish or stop hormone production.
  • Overreaction to hyperthyroidism treatment may end up lowering thyroid hormone production too much.
  • Radiation therapy may affect the thyroid gland’s ability to produce hormones.
  • Medications such as lithium may lead to hypothyroidism.
  • Pregnancy may cause women to develop hypothyroidism — either during or after pregnancy. Untreated, hypothyroidism increases the risk of premature delivery, miscarriage and preeclampsia.
  • Pituitary disorder is a rare cause of hypothyroidism in which the pituitary gland fails to produce enough thyroid-stimulating hormone (TSH).
  • Congenital disease, such as when infants are born with a defective thyroid gland or without a thyroid gland.
  • Iodine deficiency may lead to hypothyroidism.

Risk Factors

Individuals are at greater risk of developing hypothyroidism if they:

  • Are female
  • Are older than 60
  • Have a family history of thyroid disease
  • Have an autoimmune disease, such as celiac disease or type 1 diabetes
  • Have received radiation to the neck or upper chest
  • Have been treated with radioactive iodine or anti-thyroid medication
  • Have been pregnant or delivered a baby within the past six months
  • Have had thyroid surgery (partial thyroidectomy)

When to Consult a Doctor

Patients who constantly feel tired and have dry skin, constipation or previous thyroid problems should schedule an appointment with their physician.

Diagnosing Hypothyroidism

A blood test will measure the level of TSH and the thyroid hormone thyroxine. Low levels of thyroxine and high levels of TSH may indicate hypothyroidism.

Treatment Options for Hypothyroidism

Hypothyroidism may be treated with hormone therapy, which involves daily oral intake of the synthetic thyroid hormone levothyroxine to reverse the symptoms and normalize hormone levels.

Patients may also benefit from alternative medicine, such as natural extracts containing thyroid hormone derived from the thyroid glands of pigs. These products contain both thyroxine and triiodothyronine and are available by prescription only.