What Happens If Hypothyroidism Is Left Untreated?

If hypothyroidism is not treated, it can lead to various complications
If hypothyroidism is not treated, it can lead to various complications

If hypothyroidism is not treated, it can lead to various complications, such as :

  • Goiter: The lack of thyroid hormone causes constant stimulation of the thyroid gland that eventually leads to its enlargement. This is called a goiter. Goiter can cause cosmetic concerns and affect breathing and swallowing.
  • Cardiac (heart) problems: Hypothyroidism increases the risk of heart disease, causes irregular heart rate and heart failure. Hypothyroidism increases the levels of low-density lipoprotein (LDL) cholesterol, known as the "bad" cholesterol, leading to cardiovascular complications.
  • Mental health issuesDepression, slow mental function, lethargy, and poor memory can occur and may worsen over time.
  • Peripheral neuropathy: Long-term untreated hypothyroidism can damage your peripheral nerves (in the arms and legs). Patients present with pain, numbness, and tingling in the affected areas.
  • Myxedema: This is a rare, life-threatening complication of long-term, untreated hypothyroidism. Its signs and symptoms include swelling of the face and facial parts like lips, eyelids, and tongue, as well as swelling and thickening of the skin and underlying tissues. Patients also have intense cold intolerance and drowsiness followed by profound lethargy and unconsciousness.
  • Infertility: Low levels of thyroid hormone can interfere with ovulation presenting with irregular periods.
  • Birth defectsBabies born to women with untreated thyroid disease may have a higher risk of being born with birth defects. The children also have a risk of serious developmental problems. Hypothyroidism in the mother may lead to mental retardation in the child.
  • Infants: Infants with untreated hypothyroidism present at birth are at risk of serious problems regarding physical and mental development.
  • Pregnant women: Untreated hypothyroidism during pregnancy increases the risk of miscarriage, premature delivery, and preeclampsia (high blood pressure in the last trimester).

What is hypothyroidism?

Hypothyroidism occurs when the thyroid gland is unable to produce sufficient levels of thyroid hormones. The thyroid is a small, butterfly-shaped gland located in front of the neck. Thyroid hormones regulate metabolism, body temperature, heart rate, and the digestive system. A decrease in the levels of the thyroid hormone causes several body functions to slow down. Hypothyroidism tends to affect women more than men. It can begin at any age, but commonly, it affects middle-aged women. Sometimes, hypothyroidism develops after pregnancy. A thyroid problem may be diagnosed during blood tests or after symptoms begin.

There are several treatment options for hypothyroidism that are safe and effective.

What are the signs and symptoms of hypothyroidism?

The signs and symptoms of hypothyroidism in adults may include:

The signs and symptoms in babies include:

  • Yellow skin and eyes (prolonged jaundice of birth)
  • A large, protruding tongue
  • Difficulty breathing and feeding
  • Hoarse cry
  • Poor muscle tone (a protruding tummy)
  • Excessive sleepiness
  • Physical and mental retardation in untreated infants
  • Delayed milestone development

The signs and symptoms in children and young adults are the same as adults, but in addition, they may also present with:

  • Poor physical and mental development
  • Short height
  • Delayed development of permanent teeth
  • Delayed puberty


Where is the thyroid gland located? See Answer

What causes hypothyroidism?

Hypothyroidism occurs when the thyroid gland does not produce sufficient thyroid hormones. Hypothyroidism may occur due to the following:

  • Autoimmune disease: Autoimmune disease (when the body’s immune system attacks its own cells) of the thyroid is also known as Hashimoto thyroiditis.
  • Hyperthyroidism treatment: Overtreatment of hyperthyroidism (production of excessive thyroid hormone) can lower thyroid hormone levels.
  • Thyroid surgery: Removing all or a large portion of your thyroid gland.
  • Radiation therapy: Radiation therapy used to treat cancer in the head and neck region can damage the thyroid gland.
  • Medications: Certain medications used in other conditions, such as lithium for psychiatric disorders, can affect the thyroid gland.
  • Congenital disease: Being born with a defective thyroid gland or no thyroid gland.
  • Pituitary disorder: The pituitary gland produces thyroid-stimulating hormone (TSH), which stimulates the thyroid gland to produce thyroid hormone.
  • Pregnancy: Antibodies against the thyroid gland may develop during or after pregnancy (postpartum hypothyroidism).
  • Iodine deficiency: Iodine is a mineral required in the synthesis of thyroid hormones. Certain places are devoid of iodine in the soil. These regions are called goiter belts. Iodine deficiency in the foods in this region makes people prone to hypothyroidism.

How is hypothyroidism treated?

Standard treatment for hypothyroidism involves thyroid hormone tablets to achieve normal TSH levels. This is achieved by the daily administration of synthetic thyroid hormone, levothyroxine. Levothyroxine is an oral medication, and the dose is adjusted by the physician based on the hormone levels in the blood. Most cases require lifelong treatment but testing at regular intervals is advised because the hormone levels in the blood fluctuate and the dosage needs to be changed accordingly.

A balanced diet, using iodized table salt in food, and regular exercise are recommended along with the medical treatment.