Hyperthyroidism is a condition in which the thyroid gland is overactive and produces too much thyroid hormone. If left untreated, hyperthyroidism can lead to other health problems. Some of the most serious involve the heart (rapid or irregular heartbeat, congestive heart failure) and the bones (osteoporosis).
Graves disease is the most common cause of hyperthyroidism. It occurs when the immune system attacks the thyroid gland, causing it to enlarge and make too much thyroid hormone. It typically runs in families with a history of thyroid disease or other autoimmune conditions. Some people with Graves' disease also develop swelling behind the eyes that causes the eyes to bulge outward.
Your doctor will perform a physical examination and order blood tests to measure your hormone levels; we collectively call these labs thyroid function tests (TFTs) – TSH, free T4, total T3.
TSH test: TSH is a hormone released from your pituitary gland when there is not enough thyroid hormone in the system. TSH will be low if there is too much thyroid hormone (hyperthyroidism).
Free T4 and total T3 test: T3 and T4 are thyroid hormones and these will be high in hyperthyroidism.
It is important to know that biotin can interfere with the testing of thyroid function in many labs, and you should check with your doctor to see if you should stop your biotin supplement beforehand.
To determine the type of hyperthyroidism you have, your doctor may do different tests:
Treatment for hyperthyroidism will depend on its cause, your age and physical condition, and how serious your thyroid problem is. Sometimes, only observation is needed, but most of the time, some treatment is helpful. Available treatments include:
Many of the signs and symptoms of hyperthyroidism may occur in other conditions. An endocrinologist, a specialist in hormone-related conditions, can help diagnose and treat hyperthyroidism. If you have ever been treated for hyperthyroidism, or are currently being treated, see your doctor regularly so that your condition can be monitored. It is important to ensure that your thyroid hormone levels are normal and that you're getting enough calcium to keep your bones strong.
The Hormone Health Network is the public education affiliate of the Endocrine Society dedicated to helping both patients and doctors find information on the prevention, treatment and cure of hormone-related conditions.
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