The thyroid gland is a butterfly shaped gland located at the front of the neck. This gland secretes hormones that govern many of the functions in the body, such as the way the body uses energy, consumes oxygen and produces heat. Thyroid disorders typically occur when this gland releases too many or too few hormones. An over-active or under-active thyroid can lead to a wide range of health problems. Thyroid problems are often caused by autoimmune disorders, in which the immune system mistakenly attacks and destroys the body's own cells. For example, an autoimmune disorder called Graves' disease can cause the thyroid to be over-active, while one called Hashimoto's disease can make the thyroid under-active.
Hyperthyroidism is a thyroid disorder that occurs when the thyroid is overactive. It can cause several problems, including: weight loss, palpitations, tremors, irritability and anxiety, menstrual irregularities, vision problems (irritated eyes or difficulty seeing), muscle weakness, intolerance to heat and increased sweating, infertility, diarrhea or frequent bowel movements, fatigue, etc. It can be detected on the basis of signs and symptoms, along with a blood test for thyroid function, and in some cases, radioactive iodine uptake scan of thyroid. Several illnesses can cause hyperthyroidism, the most common being Graves' disease. Treatment for hyperthyroidism usually involves medication to reduce the amount of hormones produced by the thyroid or radioiodine ablation of the thyroid. In some cases, surgery to remove the thyroid may be required.
At times, similar symptoms are caused due to thyroiditis- an inflammation of the thyroid gland. It is important to distinguish it from Graves' disease as thyroiditis usually resolves on its own with time, whereas Graves' disease requires treatment.
Hypothyroidism is a thyroid disorder that occurs when the thyroid does not produce enough hormones, which is the opposite of hyperthyroidism. This can cause symptoms like weight gain, fatigue, menstrual irregularities, depression, dry skin and hair, sluggishness, constipation, etc. Hypothyroidism is often caused by Hashimoto's disease, an autoimmune disease where the body's immune system attacks the thyroid gland. This condition can be treated using a drug called T4. Most patients must stay on T4 for their entire lives, and must be closely monitored by the doctor. Thyroid function tests are required for monitoring and to guide adjustments in the T4 doses.
Thyroid disorders can also occur because of thyroid nodules, which are growths on the gland. These small growths are usually harmless and can go unnoticed for years. Doctors can sometimes feel these nodules during routine examination, or they may get detected incidentally during other investigations. At times, thyroid nodules can be cancerous. Hence, these may warrant further investigations like ultrasound of the thyroid, and fine needle aspiration of the nodule. If the nodules are not cancerous, they will not need treatment in most cases. Sometimes they need to be removed. Cancerous nodules always need to be removed, followed by treatment with radioactive iodine.
During pregnancy, thyroid hormones can affect the health of both the mother and the developing baby. Thyroid hormone levels sometimes need to be carefully monitored and adjusted, even if the expectant mother never had thyroid problems before. Those who are hypothyroid prior to pregnancy need to increase their T4 doses during pregnancy. After pregnancy, some women have abnormal levels of thyroid hormone for a year or more. Even those women who had normal thyroid hormone levels, but have antibodies positive for the thyroid, may develop abnormal levels of thyroid hormone after delivery. Hence, it is important to monitor the thyroid hormone levels even after delivery at least up to one year.