[ hi-per-THY-roy-diz-uhm ]

Hyperthyroidism is a medical condition characterized by an overactive thyroid gland, which produces an excessive amount of thyroid hormones. The thyroid gland, located in the front of the neck, plays a crucial role in regulating the body's metabolism, growth, and energy levels.

When someone has hyperthyroidism, their thyroid gland produces an excess of thyroid hormones, primarily thyroxine (T4) and triiodothyronine (T3). These hormones are responsible for regulating various bodily functions, including heart rate, body temperature, and metabolism. However, when their levels become too high, it can lead to a range of symptoms and disruptions in normal bodily processes.

The symptoms of hyperthyroidism can vary but may include rapid or irregular heartbeat, weight loss, increased appetite, nervousness or anxiety, irritability, difficulty sleeping, excessive sweating, sensitivity to heat, fatigue, muscle weakness, and changes in bowel movements. In some cases, the enlargement of the thyroid gland (known as a goiter) may also be present.

Hyperthyroidism is typically diagnosed through blood tests that measure levels of thyroid hormones, such as T4 and T3, as well as thyroid-stimulating hormone (TSH).