Hyperthyroidism (Overactive Thyroid)


An Overactive Production of Thyroid Hormone

Thyroid hormone is produced by the thyroid gland, a small, butterfly-shaped gland that helps regulate the body’s metabolism, the process of changing food into energy. Thyroid hormone influences many functions, including temperature, growth rate and fertility. If the thyroid gland produces too much thyroid hormone, a condition known as hyperthyroidism results. There are several reasons why this happens. Antibodies made by the immune system can stimulate the thyroid gland to produce too much thyroid hormone, a hyperthyroid condition known as Graves’ disease. Excess thyroid hormone may be produced if the thyroid gland is inflamed or if a tumor is present. Goiters, or nodules that form on the thyroid gland, can also cause excess hormone production. There is no way to prevent hyperthyroidism, but it can be recognized early and then treated so that normal amounts of thyroid hormone circulate in the bloodstream. Signs of hyperthyroidism include nervousness and tremor, a fast or irregular heartbeat, weight loss, diarrhea, and sweating. An annual physical exam can help detect abnormal thyroid levels and uncover signs of thyroid disease.

The thyroid gland controls many important functions in the body. The symptoms of hyperthyroidism are easy to learn and a simple blood test will diagnose the condition so that it can be treated.

The thyroid gland is located in the base of the neck, just below the Adam’s apple. The thyroid influences the function of many organs in the body, and its proper functioning is crucial to good health. About 13 million Americans have thyroid disorders. Thyroid diseases often go undiagnosed because they usually begin slowly, and the symptoms are similar to many other diseases. Hyperthyroidism, the condition that occurs when the thyroid gland produces too much hormone, is the least common thyroid condition. Factors that increase the chance of developing hyperthyroidism include having a family history of this disorder, smoking, and older age. In one type of hyperthyroidism, Graves’ disease, other autoimmune diseases may be present. The symptoms of hyperthyroidism are numerous and easy to leam, but only a doctor can make a diagnosis. A measurement of the thyroid hormones in the blood, known as a thyroid stimulating hormone (TSH) test, will uncover any thyroid imbalance. In certain cases, a radioactive scan of the thyroid gland can show how well the thyroid gland is working.

Symptoms of Hyperthyroidism: An excess of thyroid hormone will cause an increase in the metabolic rate of the body, thus leading to symptoms that indicate hyperthyroidism. Patients may complain of weight loss, weakness, diarrhea, rapid heart rate, skipped beats, nervousness, mood swings, tremors, sweating, and itching, burning or bulging eyes. Some patients cannot tolerate heat. Female patients may notice changes in their menstrual periods. A physical exam may also disclose an enlarged thyroid gland. Treatment of this condition is aimed at lowering thyroid levels in the body. Medications such as propylthiouracil (PTU), methimazole, and potassium iodide work to slow down the production of thyroid hormone. These drugs will usually regulate hormone production within 6 to 12 weeks. Beta-blockers may be prescribed to help reverse some of the effects of high thyroid levels on the body, such as rapid and irregular heart rate, but the drugs should be used with caution in patients with asthma or diabetes. In patients with Graves’ disease, radioactive iodine may be used to destroy the thyroid tissue. If a thyroid tumor is the cause of hyperthyroidism, surgery may be required to remove the tumor.

Treating Hyperthyroidism: During and after treatment, the thyroid hormone blood levels are checked and the medications adjusted. Patients who respond best to thyroid medication are those who have had the condition for less than six months or have had no previous failure with antithyroid therapy. If the thyroid gland has been destroyed from the use of radioactive sodium iodine therapy, or surgically removed, thyroid supplement medication is given to restore normal thyroid levels. If hyperthyroidism is not corrected early, and high levels of excess thyroid hormone persist, an increased metabolic rate can lead to changes in the skin, hair, and nails. Permanent eye changes can occur in patients with Graves’ disease even after treatment.

Importance of Regular Checkups: Since hyperthyroidism cannot be prevented, regular check-ups will help detect the condition and allow for early treatment. Patients should also learn the signs and symptoms of the condition to know when they should see a doctor. If they are taking thyroid medication, they should know which side effects may occur. If a patient has questions about thyroid medication, he or she should consult with the pharmacist.

US Pharmacist
Copyright 2003 Jobson Publishing, LLC