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Subclinical Hyperthyroidism

What is subclinical hyperthyroidism?

Subclinical hyperthyroidism is a condition that develops when the amount of thyroid stimulating hormone (TSH) in your blood is low. TSH is made in the brain and controls how much thyroid hormones are made. Thyroid hormones help control body temperature, heart rate, growth, and weight.

What causes or increases my risk for subclinical hyperthyroidism?

  • An autoimmune diseases is an immune system problem that may make your thyroid gland produce too much thyroid hormone. Graves disease is an example of an autoimmune disease that increases thyroid hormone.

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

  • Certain medicines , such as heart medicines used to help your heart beat normally, can cause subclinical hyperthyroidism.

What are the signs and symptoms of subclinical hyperthyroidism?

You may have no signs and symptoms, or you may have general signs and symptoms of hyperthyroidism:

  • Weight loss, increased appetite, diarrhea, or constipation

  • Increased sweating and heat intolerance

  • Nervousness, restlessness, tremors, and difficulty sleeping

  • Faster heart rate and breathing than normal for you, even at rest

  • Painful lump in your neck, or bulging eyes

  • Fatigue and muscle weakness

  • Decreased or absent monthly periods

How is subclinical hyperthyroidism diagnosed?

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

How is subclinical hyperthyroidism treated?

You may not need any treatment, or you may need any of the following:

  • Antithyroid medicines decrease thyroid hormone levels. They may also decrease and prevent the signs and symptoms of hyperthyroidism.

  • Radioactive iodine is given to damage or kill some thyroid gland cells. This may decrease the amount of thyroid hormones made by the thyroid gland. Tell your caregiver if you know or think you might be pregnant. This medicine can be harmful to an unborn baby.

  • Surgery may be done to remove all or part of your thyroid gland.

When should I contact my caregiver?

  • You have a fever.

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

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

When should I seek immediate care or call 911?

  • You have sudden chest pain or trouble breathing.

  • You faint or have a seizure.

  • Your heart is beating faster or slower than normal for you, and you are restless.

  • Your signs and symptoms return or become worse.

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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