If you are having any symptoms or have any questions, please call 811 to speak with a registered nurse 24 hours a day.

OVERVIEW

What is hypothyroidism?

Hypothyroidism is known as underactive thyroid. It occurs when your thyroid gland does not make enough thyroid hormone. It means you have low thyroid activity.  The thyroid gland is shaped like a butterfly. It is located in the front of your neck, just below your Adam’s apple. that the thyroid controls your metabolism.  It makes hormones that control how well you burn calories, your heart rate, your muscles, bones, and other organs.

SYMPTOMS

What are the symptoms of hypothyroidism?

The symptoms of hypothyroidism tend to develop slowly. Symptoms can be mistaken for stress, depression, or other health problems. Common symptoms include:

• Fatigue
• Unplanned weight gain
• Muscle weakness
• Muscle aches, cramps, tenderness or stiffness
• Increased sensitivity to cold
• Constipation
• Pale, dry skin
• Puffy face
• Hoarse voice
• Joint pain, stiffness, or swelling.
• Changes in menstrual patterns, such as heavier flow. An enlarged thyroid gland (called a goiter), which can appear as swelling at the base of the neck. Brittle hair and fingernails.
• Forgetfulness or confusion

Anyone can develop the condition, including infants and teenagers. Babies born without a thyroid gland or with a thyroid that doesn’t work properly may not have many symptoms at first. They may have yellowing of the skin and the whites of their eyes (jaundice). Their face could be puffy and their tongue may be enlarged causing choking. As the disease progresses, infants may have trouble feeding and may not grow and develop normally. They may also be constipated, sleepy, and have poor muscle tone. If it is not treated, hypothyroidism in infants can lead to physical and intellectual disabilities. In Nova Scotia and PEI, newborn infants are screened for hypothyroidism before leaving the hospital.

Children and teens who develop hypothyroidism have the same symptoms as adults, but they may also experience:

• Slow growth
• Slow mental development
• Delayed permanent teeth
• Delayed puberty

CAUSES & RISK FACTORS

What causes hypothyroidism?

The most common cause of hypothyroidism is an autoimmune disease called Hashimoto’s disease. Normally, the immune system helps protect the body against viruses, bacteria and other substances. An autoimmune disease is when your immune system produces antibodies that attack your body’s tissues and/or organs. With Hashimoto’s the immune system attacks the thyroid and keep it from producing enough hormones.

Other common causes of hypothyroidism include:

• Certain medicines
• Radiation therapy
• Thyroid surgery
• Treatment for hyperthyroidism (overactive thyroid).

Some less common causes of hypothyroidism include:

• Congenital disease: About 1 in 4,000 infants in Canada are born with a defective thyroid or no thyroid at all. Nova Scotia and PEI screen newborns for hypothyroidism before they leave the hospital.
• Pituitary disorder: The pituitary gland produces a thyroid-stimulating hormone, (TSH). This tells the thyroid gland how much thyroid hormone to produce. A pituitary disorder may keep the pituitary gland from producing the right amount of TSH to manage thyroid hormones.
• Pregnancy: Some women develop hypothyroidism during or after pregnancy. This is because their bodies produce antibodies that attack the thyroid gland. If it is not treated, hypothyroidism can jeopardize the health of both mother and baby.
• Iodine deficiency: Iodine is a mineral used by the body to make thyroid hormones. Iodine deficiency can keep the body from being able to make enough thyroid hormone. In Canada, most table salt has iodine added to it to make sure everyone gets enough.

DIAGNOSIS & TESTS

How is hypothyroidism diagnosed?

Contact your healthcare provider if you have symptoms of an underactive thyroid. They may do a blood test to measure the amount of thyroid hormone and TSH in your blood. This confirms the diagnosis.

Some healthcare providers recommend screening older women for hypothyroidism during routine physical examinations. Some also recommend screening pregnant people and those who are trying to become pregnant. This is because low amounts of the thyroid hormone can play a role in infertility.

PREVENTION

Can hypothyroidism be prevented or avoided?

There is no known way to prevent hypothyroidism. It is more common in women than men, especially those older than 60 years of age. You also are at greater risk if you:

• Have a family history of thyroid disease. Have been treated with radioactive iodine or anti-thyroid medicines
• Have received radiation therapy to your neck or upper chest
• Have had thyroid surgery

TREATMENT

Treatment for hypothyroidism is a replacement thyroid hormone.  You take the supplement daily in pill form. This medicine regulates hormone levels and helps relieve symptoms. Over time, your metabolism goes back to normal. The medicine helps to lower your LDL cholesterol and may help reverse some weight gain.

The correct medicine dose varies for each person. It may take a few tries to get the right dose. If you are not taking enough, you may continue to experience symptoms of hypothyroidism. If you are taking too much, you may have symptoms similar to those of hyperthyroidism (overactive thyroid disease). Your healthcare provider can tell how much to give based on your symptoms, blood test results, and the cause.

Some medicines and foods may affect your body’s ability to absorb the replacement thyroid hormone. Examples of medicine are iron supplements, calcium supplements, cholestyramine, and aluminum hydroxide (found in some antacids). Tell your doctor if you eat large amounts of soy products or are on a high-fiber diet.

 Living with hypothyroidism

If it is not treated, hypothyroidism can lead to other health problems. These include:

• Goiter: It is common to have an enlarged thyroid. This can cause a swollen lump on your neck called a goiter. A goiter can affect your appearance and can even make it hard for you to swallow or eat.
• Weight gain is common in people who have underactive thyroid. This is because your hormone levels affect your metabolism. Diet and exercise can help manage your weight.
• Heart disease: An underactive thyroid causes high levels of “bad” (LDL) cholesterol.
• Mental health issues: Depression that occurs with hypothyroidism can become worse over time.
• Myxedema: This is a rare, life-threatening condition. Symptoms are intense sensitivity to cold and drowsiness or severe lethargy. This can lead to unconsciousness and a coma. Contact a healthcare provider right away if you notice these warning signs.
• Birth defects: Babies born to women who have untreated hypothyroidism may have birth defects.
• Infertility: Not enough thyroid hormone can make it hard for some woman to get pregnant. An underactive thyroid also can be harmful to the mother and baby during pregnancy. Most healthcare providers test thyroid hormone levels at this stage.

FOR MORE INFORMATION

Thyroid Foundation of Canada

http://www.thyroid.ca/