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What is hypothyroidism?

Hypothyroidism is a condition that develops when the thyroid gland does not make enough thyroid hormone. Thyroid hormones help control body temperature, heart rate, growth, and weight.

What causes hypothyroidism?

  • An autoimmune disease is an immune system problem that may make your body attack your thyroid gland. Hashimoto disease is the most common autoimmune disease that causes hypothyroidism.

  • Certain medicines , such as antithyroid medicines, can cause hypothyroidism.

  • Treatments such as radiation therapy used to treat cancers of the head and neck can damage your thyroid gland. Thyroid surgery also makes you more likely to develop hypothyroidism.

  • Other thyroid problems such as an enlarged or swollen thyroid, lumps caused by infections, or thyroid cancer can affect how your thyroid works.

  • A family history of hypothyroidism or autoimmune disease can also increase your risk.

  • Low iodine levels can cause hypothyroidism because the thyroid gland uses iodine to make thyroid hormones.

What are the signs and symptoms of hypothyroidism?

The signs and symptoms may develop slowly, sometimes over several years.

  • Extreme fatigue

  • Sensitivity to cold

  • Constipation

  • Dry, flaky skin or brittle nails

  • Thinning hair

  • Muscle weakness

  • Heavy or irregular monthly periods

  • Depression or irritability

How is hypothyroidism diagnosed?

Your caregiver will ask about your symptoms and what medicines you take. He will ask about your medical history and if anyone in your family has hypothyroidism. You will have blood tests to check your thyroid hormone level.

How is hypothyroidism treated?

Thyroid replacement hormone will bring your thyroid hormone level back to normal. Ask your caregiver for more information on other medicines you may need.

When should I contact my caregiver?

  • You have a fever.

  • You have chills, a cough, or feel weak and achy.

  • You have pain and swelling in your muscles and joints.

  • Your skin is itchy, swollen, or you have a rash.

  • You have questions or concerns about your condition or care.

When should I seek immediate care or call 911?

  • Your signs and symptoms return or get worse, even after treatment.

  • You have diarrhea, tremors, or trouble sleeping.

  • Your legs, ankles, or feet are swollen.

  • You feel like you are going to faint.

  • You have a seizure.

  • You have sudden chest pain or shortness of breath.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

© 2015 Truven Health Analytics Inc. Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes. All illustrations and images included in CareNotes® are the copyrighted property of A.D.A.M., Inc. or Truven Health Analytics.

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