Symptoms of an overactive thyroid

The thyroid is a butterfly-shaped gland that is located at the base of the neck, and produces thyroid hormones. These hormones control many of the body’s activities, such as heart rate and how quickly calories are burned. The activities regulated by these thyroid hormones are what make up the body’s metabolism.

Hyperthyroidism is the condition of having an overactive thyroid. With this condition, the body produces more thyroid hormones than needed.

Symptoms of hyperthyroidism include:

Anxiety, nervousness and irritability;
Brittle hair;
Difficulty sleeping;
Frequent bowel movements;
Hand tremors;
Increased appetite;
Mood swings;
Muscle weakness or fatigue, specifically in the upper arms and thighs;
Rapid and/or irregular heartbeat;
Sensitivity to heat;
Lightened and/or infrequent menstrual periods;
Sudden weight loss; and
Sweating.

Graves’ disease is the leading cause of an overactive thyroid, accounting for approximately 70% of cases. Graves’ disease tends to run in families and causes the thyroid gland to overproduce thyroid hormones. With Graves’ disease, one or both eyes may bulge, or the eyes may appear enlarged. There may also be a swelling of the front of the neck, known as goiter.

Toxic nodular, also known as multi-nodular goiter, is another type of hyperthyroidism. This condition causes one or more nodules or lumps to gradually grow in the thyroid and increase its activity, producing more thyroid hormone in the blood than is necessary. Thyroiditis, though not caused by an overactive thyroid, causes stored thyroid hormone to leak from the gland. Thyrotoxicosis occurs when there is excess thyroid hormone in the blood.

A diagnosis of hyperthyroidism is usually done through both a physical exam and laboratory tests. A doctor will check for an enlarged thyroid gland, fast heartbeat, hand tremors and smooth or moist skin. The doctor may order lab tests to measure for the amount of thyroid hormones and thyroid-stimulating hormones in the blood.

Hyperthyroidism is treated in a variety of ways depending on the individual. Treatment options include:

Antithyroid drugs — such as methimazole (Tapazole, Pfizer) or propylthiouracil (PTU) — prevent the thyroid from producing more hormones.
Beta-blockers reduce the symptoms of a racing heart, the shakes and nervousness but do not decrease the level of thyroid hormones.
Radioactive iodine kills overactive thyroid cells, but may take months to work, so antithyroid drugs are often prescribed in the meantime.
Surgery involves removal of part of the thyroid. First antithyroid or beta-blocking drugs are given to control hyperthyroidism. Fewer than 1% of patients experience complications when an experienced surgeon performs the surgery.

Additional information may be found at these websites:

http://www.nlm.nih.gov/medlineplus/hyperthyroidism.html

http://www.thyroid.org/wp-content/uploads/patients/brochures/HyperthyroidismFAQ.pdf

http://www.thyroid.org/faq-hyperthyroidism/

http://www.thyroid.org/wp-content/uploads/patients/brochures/Hyper_brochure.pdf