Symptoms, Causes and Treatment of Hypothyroidism

The thyroid is a gland located in the lower front part of your neck, and it releases hormones that affect virtually every part of the body from metabolism and temperature regulation to heartbeat and how well your body burns calories. Without enough thyroid hormone—a condition known as hypothyroidism (or underactive thyroid)—several of these processes will slow down.

Hypothyroidism upsets the typical balance of chemical reactions, and over time, it can lead to several health issues if left untreated. Fortunately, there are accurate tests to diagnose hypothyroidism and safe and effective treatments for it.

Symptoms

Symptoms of hypothyroidism vary depending on the severity of the hormone deficiency, but they generally develop slowly over a period of years. Symptoms often begin very mildly and develop further as your metabolism slows. Symptoms can include:

Fatigue
Sensitivity to cold
Constipation
Dry skin
Weight gain or puffy face
Hoarseness
Weakness, aches, tenderness or stiffness in muscles
Elevated cholesterol
Pain, stiffness or swelling in joints
Heavier menstrual periods (in women)
Thinning hair
Impaired memory or slowed processes
Slowing heart rate
Depression
Poor growth, mental development or delayed puberty (in children and teens)
Delayed development of permanent teeth (in children and teens)

In infants, other symptoms to look for can include:

Jaundice: A yellowing of skin and whitening of the eyes
Frequent choking
A large, protruding tongue
Puffy face
Constipation
Poor muscle tone
Extreme sleepiness

Even mild cases of hypothyroidism can lead to severe physical and mental retardation in infants. Complications of untreated cases in adults include goiter, heart problems, mental health issues, peripheral neuropathy, myxedema (long-term, undiagnosed hypothyroidism that can be life-threatening), infertility and birth defects.

Causes and Risk Factors

There are a number of possible factors that cause the thyroid to not produce enough hormones. Some of the most common include:

Autoimmune disease: The most common cause of hypothyroidism is a specific inflammatory disorder called Hashimoto’s thyroiditis. Autoimmune disorders occur when the immune system produces antibodies that attack the body’s own tissues, preventing the thyroid from producing the proper hormones.
Hyperthyroidism treatment: People with hyperthyroidism, an inverse condition where too much thyroid hormone is produced, are often treated with medications to normalize thyroid functions. In some cases, though, this can cause hypothyroidism.
Thyroid surgery: In cases where part or all of the thyroid gland is removed, patients may need to take thyroid hormone for the rest of their lives.
• Radiation therapy: When used on the head or neck, radiation therapy can affect thyroid hormone production.
• Medications: Ask your doctor about whether any medications you take could contribute to hypothyroidism.

In rarer cases, hypothyroidism can be caused by:

Congenital disease: Some babies are born with a defective thyroid gland or with no thyroid gland at all.
Pituitary disorder: A rare cause is a failure of the pituitary gland to produce enough thyroid-stimulating hormone.
Pregnancy: Some women develop hypothyroidism during or after pregnancy. Left untreated during pregnancy, this can impact the fetus and increase the chances of complication.
Iodine deficiency: Iodine is a mineral vital to thyroid hormone production, and while rare, there are parts of the world where iodine deficiency is common.

Anyone can develop hypothyroidism, but there are a few factors that make it more likely:

Age and gender: Women over 60 are at the highest risk
Autoimmune disease
Family history of thyroid disease
Treatment with radioactive iodine or anti-thyroid medications
Radiation therapy
Thyroid surgery
Pregnancy within the last six months

Treatment

Hypothyroidism is diagnosed using a blood test called the TSH test, which is very sensitive and can often pick up the condition before symptoms are even noticeable.

Standard treatment for hypothyroidism involves daily use of a synthetic hormone called levothyroxine, which restores hormone levels and reverses symptoms. These treatments cause virtually no side effects when used in the proper dosages—though finding these dosages can take a bit of time in some cases. Certain supplements, medications and foods might limit the body’s ability to process levothyroxine, and your doctor will talk to you about these if necessary.

If you’re showing the signs of hypothyroidism, your doctor will inform you on the appropriate course for diagnosis and treatment.