Hyperthyroidism or overactive thyroid occurs when T3 (triiodothyronine) and T4 (tetraiodothyronine) levels are higher and TSH levels are lower than normal. There are many causes of hyperthyroidism. Graves’ disease, an autoimmune disorder, is the common cause of hyperthyroidism.
OTHER CAUSES OF HYPERTHYROIDISM ARE
• excess iodine, a key ingredient in T4 and T3
• thyroiditis, or inflammation of the thyroid, which causes T4 and T3 to leak out of the gland
• tumors of the ovaries or testes
• benign tumors of the thyroid or pituitary gland
• large amounts of tetraiodothyronine taken through dietary supplements or medication.
SIGNS AND SYMPTOMS OF HYPERTHYROIDISM OR OVERACTIVE THYROID
High T3 and T4 levels cause excessively high metabolic rate which causes weight loss, increased sweating, and low tolerance to heat and irregular menstrual cycle in women.
Other symptoms are
• nervousness, anxiety
• difficulty sleeping
• increased appetite
• intolerance to heat
• muscle weakness, fatigue
• frequent bowel movements
• tachycardia – increased heart rate
• arrhythmia – irregular heartbeat
• fine, brittle hair
• skin thinning
• mild tremors – fine tremors in hands
• Enlarged thyroid gland, which appears as a swelling at the base of the neck.
Hyperthyroidism, particularly Graves' disease, tends to run in families and is more common in women than in men.
The diagnosis is done through clinical signs and symptoms, unexplained weight loss though having proper food, increased heart rate, sleeplessness, etc., and confirmation by blood tests for TSH, T3, T4 levels.
TREATMENT OF HYPERTHYROIDISM
Hyperthyroidism can be treated with antithyroid medications that interfere with the production of thyroid hormones (primarily methimazole).
Another option is radioactive iodine therapy to damage the cells that make thyroid hormones.
SURGERYIn rare cases in which women do not respond to or have side effects from these therapies, surgery to remove the thyroid (either one part of the entire gland) may be necessary.
The choice of treatment will depend on the severity and underlying cause of your symptoms, your age, whether you are pregnant, other conditions you may have, and the potential side effects of the medication.