The thyroid gland is a butterfly-shaped organ on the front of the neck, around the windpipe, that releases hormones involved in regulating several processes in the body, including metabolism, heart rate, blood pressure, body temperature, and bone function. Improper functioning of the thyroid gland can be very damaging to your health, causing irregular heartbeat, weight loss or gain, fatigue/tiredness, anxiety and irritability, irregular menstrual periods, hair loss, heat or cold sensitivity, memory problems, and vision problems. There are several thyroid disorders, which will either cause increased or decreased levels of thyroid hormones. Examples of possible disorders include goitre (enlarged thyroid gland), thyroid nodules (non-cancerous lumps in the gland), thyroid cancer, thyroiditis (inflammation of thyroid gland), hypothyroidism (decreased thyroid hormone levels), hyperthyroidism (increased thyroid hormone levels), and thyrotoxic crisis/thyroid storm. Thyroid storm is a serious, potentially life-threatening complication of hyperthyroidism that usually requires hospitalization for symptom treatment. Some thyroid disorders are autoimmune, meaning an overactive immune system causes antibodies that attack the thyroid gland. Grave’s Disease is autoimmune hyperthyroidism, and Hashimoto’s Thyroiditis is autoimmune hypothyroidism. Thyroid disorders are very common and can affect people of all ages.
Most thyroid diseases will require medication therapy. In thyroid cancer, nodules, or goitre, surgery may be necessary. In some cases, changes in diet can help manage hypothyroidism or hyperthyroidism symptoms. Iodine is an element found in the diet that impacts thyroid function. Sometimes, thyroid cancer or extreme hyperthyroidism may require the removal of the thyroid gland or chemical destruction/deactivation of thyroid tissue. This may then result in hypothyroidism, which requires medication to increase thyroid hormone levels. Fortunately, several medication treatments for thyroid disorders are available.
-Radioactive Iodine is given orally and is taken up by thyroid cells after it enters the bloodstream, where it will destroy the overactive thyroid tissue. It is used to treat an overactive thyroid gland, and in higher doses, to treat thyroid cancer. This treatment is usually very effective but requires the patient to avoid direct contact with others for a few days during and after treatment to reduce possible radiation exposure. Thyroid cells are the only tissue in the body that will absorb radioactive iodine, so it will not affect any other parts of the body. R-131 is the radioactive iodine medication used.
-Beta Blockers are cardiac medications used to reduce blood pressure and regulate heart rate. They do not treat hyperthyroidism itself but are used to help control symptoms of fast heart rate, high blood pressure, and anxiety. Examples of beta blockers used in hyperthyroidism include propranolol, nadolol, acebutolol, metoprolol, and atenolol.
-Iodides are used to provide iodine that binds to receptors in thyroid gland cells and stops the release of thyroid hormones. This is a temporary fix for hyperthyroidism that only works for a few days to two weeks, but it is used in patients awaiting surgery to remove the thyroid gland and in treatment of thyroid storm. Examples of iodides used in hyperthyroidism are potassium iodide solution (SSKI) and Lugol’s solution.
-Antithyroid Drugs are oral medications containing molecules that block the synthesis/creation of thyroid hormones to decrease their levels in patients with hyperthyroidism. They are the mainstay of treatment for hyperthyroidism. Examples of antithyroid drugs include methimazole, carbimazole, and propylthiouracil (PTU).
-Levothyroxine is a synthetic (man-made) version of the thyroid hormone, thyroxine, also known as T4. It is used to replace and increase levels of thyroid hormone in hypothyroidism and is the treatment of choice. Since the dose is so small, GI absorption of levothyroxine can be easily interrupted by food or other medications, affecting the dose that gets into the body. Therefore, it is important that levothyroxine is taken on an empty stomach with a full glass of water.
-Liothyronine is the synthetic version of another thyroid hormone, triiodothyronine, also known as T3. It is sometimes used in patients who do not have an adequate response to treatment with levothyroxine. It is always used in addition to levothyroxine. Because it has a short duration of action in the body, it must be taken twice a day.
-Desiccated thyroid extract is dehydrated pork thyroid gland that is made into a tablet. Some people believe that since it contains natural thyroid, it is the best replacement for low thyroid hormone levels. However, it is important to note that there will be variations in the T3 and T4 content from batch to batch in manufacturing this product because it is a natural product. Levothyroxine is still the first-line therapy recommendation.
Most of the time, there are not a lot of side effects with medications used for thyroid, because they are simply replacements for a natural hormone, or they suppress the action of the natural thyroid hormones. Rarely, a patient may be allergic to an inactive ingredient in the medication. Signs of an allergic reaction include rash, hives, swelling, trouble breathing, tightness in the throat or chest, and nausea/vomiting. If more than one of these symptoms is present at the same time, or you have trouble breathing or tightness in the throat or chest, seek medical attention right away.
Side effects most commonly seen in patients taking medications for thyroid disorders are related to over- or undertreatment, so symptoms of hypothyroidism or hyperthyroidism, as discussed above, may be present. If you are experiencing these symptoms, you may need to contact your medical provider to have hormone levels checked and/or adjust your dosage.
Long-term low or high thyroid hormone levels can have serious complications. For example, high thyroid hormone levels can lead to osteoporosis (brittle bones that break easily) and thyroid storm, and low thyroid hormone levels can lead to heart problems, infertility, or pregnancy complications. If you are pregnant or planning to become pregnant, you may need a dose adjustment. With the exception of radioactive iodine, it is safe to continue taking thyroid medications during pregnancy. It is important to let your doctor know of any other medications you are taking because there are several possible drug interactions with these medications. You should also take these drugs exactly as prescribed for the best treatment results and follow up with your doctor regularly to have thyroid hormone levels checked to ensure proper treatment.