Thyroid

• Thyroid gland function


  Produce thyroid hormones
• Classes of drugs used to treat thyroid disease


  • Thyroid replacement hormones
  • Antithyroid medications
• Hypothyroidism


  1. Inadequate thyroid hormone production

  2. Myxedema

  3. Myxedema coma

  4. Congenital hypothyroidism
• Hyperthyroidism


  1. Excess production of thyroid hormones

  2. Graves' disease

  3. Nodular goiter

  4. Thyroiditis

  5. Thyroid carcinoma

  6. Overdoses of thyroid hormones

  7. Tumors of the pituitary gland
• Myxedema


  • Hypothyroidism that occurs during adult life
• Myxedema coma


  • Severe form of hypothyroidism that can occur as the culmination of severe, long-standing hypothyroidism or be precipitated by an acute event in a poorly controlled hypothyroid patient, such as infection, myocardial infarction, cold exposure, or the administration of sedative drugs, especially opioids
• Congenital hypothyroidism


  • Child is born without a thyroid gland or with a gland that is hypoactive
• Graves' disease


  • Disorder that may cause hyperactivity of the thyroid gland
• Treatment of hypothyroidism


  1. Replacement of thyroid hormones

  2. Dosage of thyroid hormone is adjusted until serum levels of the thyroid hormones are within the normal range
• Types of treatment for thyroid diseases

  • Subtotal thyroidectomy
  • Radioactive iodine
  • Antithyroid medications
• Thyroid hormone replacements


  • Levothyroxine (T4)
  • Liothyronine (T3)
  • Liotrix
  • Thyroid USP
• Antithyroid agents


  • Radioactive iodine
  • Propylthiouracil
  • Methimazole
• Nursing assessment for patients with thyroid disorders


  1. Take a history of treatment prescribed

  2. Ask for specific information regarding treatment for any cardiac disease or adrenal insufficiency

  3. Ask for description of current symptoms
• Laboratory and diagnostic studies


  • Total thyroxine (TT4)
  • Total triiodothyronine (TT3)
  • Free thyroxine (FT4)
  • Free triiodothyronine (FT3)
  • TSH levels
  • TRH stimulation test
  • Thyroid autoantibodies
  • Thyroglobulin
  • Calcitonin assay
  • Ultrasound
  • Fine-needle biopsy
  • Radioactive iodine uptake
  • Electrocardiography
  • Thyroid scan
• Nursing implementation for hyperthyroid individual


  1. Provide a cool, quiet, structured environment

  2. Provide support and give directions slowly and with patience
• Nursing implementation for hypothyroid individual


  1. Provide a warm, quiet, structured environment

  2. Provide support and give directions slowly and with patience
• Nutrition for hyperthyroid individual


  • High-calorie diet of 4000 to 5000 calories, note no caffeine products
  • If diarrhea is present, note any foods with a laxative or stimulating effect
• Nutrition for hypothyroid individual


  • Low-calorie diet with increased bulk to alleviate constipation
  • Encourage adequate fluid intake, unless comorbidities prohibit it
• Nursing implementation for medications


  1. Stress the need for lifelong medications for the treatment of hypothyroidism

  2. Stress that several medications interact with thyroid drugs

  3. Provide detailed instructions on prescribed medications
• Psychosocial for patients with thyroid disorders


  The patient may have had a major personality change, may be depressed, or may be hyperactive
• Thyroid replacement hormones


  Hormones extracted from animal thyroid glands or synthetically manufactured to be equivalent to natural thyroid hormones
• Triiodothyronine and thyroxine


  • Normally secreted from the properly functioning thyroid gland
  • Thyroxine is partially metabolized to triiodothyronine, so therapy with thyroxine provides physiologic replacement of both hormones
• Forms of thyroid hormone replacement

  • Synthetic levothyroxine (T4)
  • Liothyronine: synthetic form of the natural thyroid hormone T3
  • Liotrix: synthetic mixture of levothyroxine and liothyronine in a ratio of 4:1, respectively
  • Thyroid USP (desiccated thyroid): derived from pig, beef, and sheep thyroid glands
• Nursing implications for thyroid hormone replacement therapy


  1. Record baseline vital signs, including apical pulse, weight, and bowel elimination patterns

  2. Assess for signs of hyperthyroidism

  3. Ensure that laboratory studies have been completed before administration of the medication
• Administration of thyroid hormone replacement

  1. Adult: PO: Therapy may be initiated with low dosages of levothyroxine, such as 50 to 100 mcg daily

  2. Dosages are gradually increased over the next few weeks to an average daily maintenance dosage of 100 to 200 mcg daily

  3. The dose should be taken on an empty stomach at least 45 minutes before ingestion of food
• Iodine-131


  Radioactive isotope of iodine
• Uses of iodine-131


  • Older patients who are beyond the childbearing years
  • Those with severe complicating diseases (e.g., heart disease)
  • Those with recurrent hyperthyroidism after previous thyroid surgery
  • Those who are poor surgical risks
  • Those who have unusually small thyroid glands
• Administration of radioactive iodine


  1. Avoid spills! Report any accidental contamination at once to the supervisor and follow directions for the institution's contamination cleanup technique, and then complete an incident report

  2. Minimize exposure as much as possible

  3. Maintain hazardous medication precautions according to the institution's policy

  4. Wear latex gloves whenever

  5. If the radioactive iodine or the patient's urine or feces spills, follow institutional policy