Common Name/Other Name
Overactive thyroid disease (Eng.)
Hyperthyroidism is a condition due to an overactive thyroid gland that produces thyroid hormones in excess amounts. High levels of thyroid hormones accelerate the body’s metabolism which causes the characteristic symptoms of hyperthyroidism. However, the symptoms of hyperthyroidism resemble other diseases making it difficult to diagnose it early. Also, beta blockers mask the signs of hyperthyroidism.
Several conditions can cause hypothyroidism. This includes:
- Graves' disease. Graves' disease is an autoimmune disorder. The body produces antibodies that attack the thyroid gland which leads to an excess production of the thyroid hormones. The antibodies can also attack tissues behind the eyes causing Graves' ophthalmopathy. Graves' dermopathy occurs when the antibodies attack the skin especially over the shin.
- Hyperfunctioning thyroid nodules. Conditions such as toxic adenoma, toxic multinodular goiter and Plummer’s disease have benign tumors that might release high amounts of thyroid hormones.
- Thyroiditis. The thyroid gland can become inflamed without an apparent cause. This can cause the leakage of stored thyroid hormones into the bloodstream.
- Medications. Some medications such as amiodarone contain iodine. An increased level of iodine in the body causes excess production of the thyroid hormones.
Diagnosis of hyperthyroidism is based on the medical history, physical exam and results of the blood test. Hyperthyroidism presents with high levels of thyroxine and low or lack of thyroid-stimulating hormone (TSH). Other tests such as radioiodine uptake test and thyroid scan can be used to determine the cause of the hyperthyroidism.
Commonly Prescribed Drugs
- Radioactive iodine. Radioactive iodine is taken by mouth and absorbed by the thyroid gland. The thyroid gland shrinks and symptoms disappear within several months. However, this treatment can cause hypothyroidism and require the daily intake of thyroxine. Patient who took radioactive iodine should minimize prolonged contact with other people for a few days or weeks. Women should not get pregnant for at least 6 months and men should not father a child for at least 4 months after the treatment.
- Anti-thyroid medications. Anti-thyroid medications control the production and release of hormones by the thyroid gland. Improvement of symptoms can be observed within 6 to 12 weeks of treatment. The most common medications are propylthiouracil and methimazole. Propylthiouracil is less preferred because of more reported cases of liver damage.
- Beta blockers. Beta blockers do not address the excessive thyroid hormones, but it resolves some of the symptoms. It slows down the heart rate and prevents palpitations. Propranolol is a beta blocker given to patients with hyperthyroidism.
Treatment and Management
Calcium and vitamin D supplementation are encouraged to prevent brittle bones. The recommended daily dose of calcium for adults ages 19 to 50 and men ages 51 to 70 is 1,000 mg. women older than 50 and men older than 70 should receive 1,200 mg of calcium each day. Daily vitamin D levels should reach 600 IU for adults ages 19 to 70 and 800 IU for adults older than 70.
Apply cool compress on the eyes to provide extra moisture.
Protect protruding eyes from sunlight and UV rays using sunglasses.
Lubricating eye drops can reduce dryness and itchiness of the eyes.
When lying down, place the head higher than the rest of the body to minimize swelling of the eyes.
- Thyroidectomy. For patients who cannot tolerate anti-thyroid medications or radioactive iodine, a treatment option is the removal of most of the thyroid gland. The surgery can damage the vocal cords and the parathyroid glands. Since the body will not be able to produce adequate thyroid hormones, lifetime treatment of levothyroxine is required.
Surgical procedures can be done on patients with Graves' ophthalmopathy.
- Orbital decompression surgery. The bone between the eye socket and sinuses is removed to provide more space for the eyeballs to return to normal position. A complication of the surgery includes double vision.
- Eye muscle surgery. Eye muscle surgery helps correct double vision caused by Graves' disease. The surgery involves cutting and reattaching of the eye muscles.