Thyroid Disorders &Treatment Hyperthyroidism

Racing the Engine - Hyperthyroidism

This is the third most common thyroid problem in the US

Hyperthyroidism is a condition in which the thyroid gland produces too much thyroid hormone. Every year, some 350,000 people develop some kind of hyperthyroidism, and it is eight to ten times more common in women than men.

If you develop hyperthyroidism, you may experience rapid and/or irregular heartbeat, tremors, weakness, heat intolerance, weight loss, mood swings, and more frequent bowel movements. Women may have lighter, less frequent menstruation. A related problem in 5% of patients involves the eyes, which can appear enlarged and bulging.

Most common cause

The most common cause (in the US, 70 to 80%) is Graves' disease, also called diffuse toxic goiter. This is an autoimmune disease in which your immune system overstimulates your whole gland to make too much hormone. About 5% of patients with Graves' disease also have some involvement with their eyes in which the eyes may become inflamed and appear enlarged. This is described as thyroid eye disease or "exophthalmos" in the articles about Graves' disease.

Ten percent of hyperthyroid patients have one or more small benign tumors in their gland, so-called "hot nodules," which make hormone at too high a rate. This is called toxic nodular goiter.

Diagnosis

The diagnosis of hyperthyroidism of any type includes a test for thyroid stimulating hormone (TSH) from the pituitary gland, which will be low, its manufacture and release turned off by high thyroid hormone levels. Thyroid hormone levels of thyroxine (T4) and triiodothyronine (T3)are increased and indicate the degree of hypothyroidism. A radioactive scan or ultrasound may be needed to determine whether overactive thyroid nodules are the cause of the hyperthyroidism.

Treatment

Treatment (in the short term) may focus on making the body less responsive to the stimulus given by the thyroid hormone, using beta adrenergic blocking agents like atenolol or propranolol. These help slow the pulse and calm your tremors and nerves. Other treatments may shut off iodine from the gland with antithyroid agents such as methimazole (Tapazole) or propylthiouracil (PTU), so it then makes less hormone.

Long-term treatment

Long-term treatment can reduce the number of hormone-making cells in the gland by using radioactive iodine, or alternatively a surgeon can remove part or all of the gland or the overactive "hot" nodules. If you are then producing too little hormone, it is easy to restore you to normal with a daily dose of thyroid hormone in pill form.

Less common causes

Less common causes include:

Subacute thyroiditis, in which your whole gland becomes inflamed, and hormone leaks out of the gland. This usually clears up in two or three months, but before it does hyperthyroidism may be followed by one or more months of underactivity of the gland (hypothyroidism).
Overmedication with thyroid hormone can also cause hyperthyroidism. Some people may try this as an aid in trying to lose weight. This is dangerous because of the risk of heart problems including a rhythm change or heart attack.
Postpartum thyroiditis is the term used when a thyroid inflammation after pregnancy causes hyperthyroidism and/or hypothyroidism in the first 3-12 months after pregnancy. Although it is relatively common (following 5% of pregnancies) it's often missed in the confusion and physical changes going on following childbirth.
Too much iodine, perhaps from kelp or seaweed, from mineral supplements, betadine douches, or even x-ray dyes can also cause hyperthyroidism occasionally, especially in individuals with overactive nodules.
Cancer in the thyroid can cause hyperthyroidism, but this is very rare.

Did you know that some people with Graves' or Hashimoto's disease also have a tendancy to certain kinds of tendon and joint inflammation?