What is hyperthyroidism?
Hyperthyroidism is a condition in which the thyroid gland produces too much thyroid hormone. When this occurs, the body’s metabolism is increased, which can cause a variety of symptoms (anxiety, weakness, tremors, fatigue, perspiring a lot, and rapid heartbeat, increased appetite, weight loss, & loose bowel movements). Mild cases may cause no symptoms but may lead to osteoporosis or heart irregularities (if not treated).
What causes hyperthyroidism?
The major causes of hyperthyroidism are:
1. Graves Disease: In Graves disease, the immune system mistakenly produces a protein (called antibody) that stimulates the thyroid to make too much thyroid hormone. Some people may develop eye problems as well.
2. Thyroid Nodules (Nodular Goitre): One or more “lumps” on the thyroid can sometimes produce too much thyroid hormone.
3. Thyroiditis: There are autoimmune conditions in which the thyroid gland may become TEMPORARILY inflamed and therefore release too much thyroid hormone into the blood, causing hyperthyroidism. These symptoms may last for several weeks and are followed by recovery to normal functions or sometimes several months of hypothyroid (low thyroid) symptoms.
4. Overtreatment: Because thyroid hormone can increase energy level & may cause weight-loss, some physicians may prescribe and some patients may take higher than required doses of thyroid hormone. Any beneficial effect is usually ‘short-lived’ and may lead to dangerous heart rhythm problems (including Atrial Fibrillation – which increases your risk of strokes) and osteoporosis (fragile bones & fractures).
How is hyperthyroidism diagnosed?
1. Blood Test: Thyroid hormone level is high (T4 & T3 are the two thyroid hormones) and TSH (the pituitary hormone which helps the brain regulate the thyroid gland) is low. (TSH test is usually the first one to become abnormal in hyperthyroidism and in mild cases a low TSH may be the only lab abnormality).
2. Thyroid Scan: Pictures (special x-rays) of the thyroid are taken after the patient ingests radioactive iodine. This test helps differentiate between different causes of hyperthyroidism and helps decide between treatment options. Do not take vitamins or iodine, before the scan.
Treatment of Hyperthyroidism:
1. β-Blockers: These medicines (e.g. Atenolol, Propranolol or Metoprolol/ Toprol) are used to control many of the bothersome side effects of hyperthyroidism (particularly rapid heart rate, anxiety or tremors. They do not reduce thyroid hormone production, however.
2. Anti-Thyroid Medications (e.g. METHIMAZOLE (TAPAZOLE) or PTU): These medications decrease the amount of thyroid hormone produced by the thyroid gland and are useful in Graves disease. The full course typically involves taking these medications for 1-2 years. They are effective in most patients while the patients are on them, but at least 50% of the patients experience a recurrence of hyperthyroidism once they stop taking them. These medications can be used to decrease thyroid hormone levels before radioactive iodine treatment as well. Side effects may include allergic reaction (rash), liver problem or very rarely (one in 500 cases) a serious reaction involving bone marrow, which may lower resistance to infections. If you develop fevers, or severe sore throat occurs while on antithyroid drugs, you should immediately stop the medicine and call your physician. Please read the instructions provided by your pharmacist carefully.
3. Radioactive Iodine: Destroying the thyroid with iodine, called radioactive iodine ablation, is a permanent way to resolve hyperthyroidism in Graves disease and hyperactive (or hot) thyroid nodules. The amount of radiation used is small and does not cause cancer or any other significant side effects. In fact, it is the most commonly used treatment for Graves disease in the U.S. The effects take 6-8 weeks. Most patients who receive radioiodine Rx become hypothyroid. Therefore, regular blood tests are recommended during the first year after radioiodine ablation and if / when low thyroid develops, you will need to take thyroid hormone.
4. Surgery: Another permanent or definitive treatment of hyperthyroidism is the surgical removal of the thyroid. This option is preferable when the thyroid gland is large, hyperthyroidism is recurrent, and a good thyroid surgeon is available. Before surgery, an antithyroid drug or a beta-blocking drug is taken to control your hyperthyroidism. Major complications of thyroid surgery occur in less than 1%of patients operated on by an experienced thyroid surgeon. During surgery, most of the thyroid gland is removed to control hyperthyroidism. Damage to the parathyroid glands (that control your body’s calcium levels) and to the nerves that control your vocal cords (which would cause you to have a hoarse voice) can occur rarely.
More information is available at: www.thyroid.org & www.endocrineweb.com
This information is for general knowledge & is not a substitute for medical advice your doctor recommends
We are not your healthcare provider, and your use of this website does not establish a patient-client relationship. All the information contained on this website is for informational purposes only. No material on this site is intended to be a substitute for professional medical advice (diagnosis, treatment, testing or nutritional information). Always seek the advice of your physician or qualified healthcare provider with any questions you may have regarding medical or health-related conditions or treatment. Your healthcare provider knows your condition or situation well and can give you specific advice which would be appropriate for your condition/situation. Your healthcare provider can also guide you more accurately about injection techniques, dietary interventions and the use of medical technology that is most pertinent and suitable for you. Please do not disregard professional medical advice or delay in seeking it because of something you may have read on this website.