Hyperthyroidism and Hypothyroidism

General Information | Risk Factors and Symptoms | Diagnosis and Treatment

General information General Information

About Hyperthyroidism and Hypothyroidism

Women are more at risk for thyroid disease than men.

The thyroid is a small, butterfly-shaped gland located at the base of the neck, below the Adam’s apple. The thyroid only weighs about an ounce but can have a tremendous impact on your health. The thyroid’s function is to create thyroid hormone. This hormone regulates every aspect of your metabolism.


Hyperthyroidism is caused by an over-active thyroid that produces too much thyroid hormone. This can accelerate the metabolism. A faster metabolism can cause sudden weight loss, a rapid or irregular heartbeat, sweating, and nervousness or irritability.


With hypothyroidism, the thyroid produces too little thyroid hormone. Symptoms of this condition vary significantly, depending on how little hormone is made. Common symptoms include sensitivity to cold, constipation, dry skin, unexplained weight gain, muscle weakness, and depression.

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Risk factors and symptoms Risk Factors and Symptoms

Risk Factors for Hyperthyroidism and Hypothyroidism

A recent pregnancy can cause hyperthyroidism or hypothyroidism.

Following are risk factors for hyperthyroidism and hypothyroidism:


Following are some risk factors for developing hyperthyroidism:

  • Being female
  • Family history of hyperthyroidism
  • Recent pregnancy (within 9 months)
  • Enlarged thyroid
  • Thyroid nodules
  • Thyroid cancer
  • Radiation exposure (i.e. radiation therapy)
  • Current or past autoimmune disease
  • Certain viral infections


Following are some risk factors for developing hypothyroidism:

  • Being female
  • Aging
  • Family history of hypothyroidism
  • Recent pregnancy (within 9 months)
  • Current or past autoimmune disease

Reducing the Risk

There are no known ways to reduce the risk of developing hyperthyroidism or hypothyroidism.

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Symptoms of Hyperthyroidism and Hypothyroidism

Following are symptoms for hyperthyroidism and hypothyroidism:


Following are some of the symptoms of hyperthyroidism:

  • Sudden, unexplained weight loss
  • Rapid or irregular heartbeat
  • Nervousness or irritability
  • Hand tremors
  • Sweating
  • Fine, brittle hair
  • Changes in menstrual patterns
  • Increased bowel movements
  • Increased sensitivity to heat
  • Enlarged thyroid gland (goiter)
  • Fatigue
  • Difficulty sleeping


Following are some of the symptoms of hypothyroidism:

  • Increased sensitivity to cold
  • Constipation
  • Dry skin and hair
  • A puffy face
  • Hoarse voice
  • An elevated blood cholesterol level
  • Unexplained weight gain
  • Muscle aches, especially in your shoulders and hips
  • Pain, stiffness, and swelling in your joints
  • Muscle weakness or cramping
  • Heavier than normal menstrual flow
  • Depression
  • Enlarged thyroid gland (goiter)

Diagnosis and treatment Diagnosis and Treatment

Diagnosing Hyperthyroidism and Hypothyroidism

A thyroid uptake and scan are often performed to help diagnose hyperthyroidism. The uptake test checks how much of and how evenly a radioactive substance is absorbed by the thyroid. A thyroid scan uses a small amount of radioactive material and a special camera to further measure thyroid function and identify abnormal areas in the thyroid.

Treating these Conditions

Radioactive iodine therapy is used to treat hyperthyroidism. A radioactive form of iodine is administered and absorbed by thyroid tissue. This iodine causes the gland to shrink.

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