Hyperthyroxinemia is a

thyroid disease Thyroid disease is a medical condition that affects the structure and/or function of the thyroid gland. The thyroid gland is located at the front of the neck and produces thyroid hormones that travel through the blood to help regulate many other ...

where the serum levels of

thyroxine Thyroxine, also known as T4, is a hormone produced by the thyroid gland. It is the primary form of thyroid hormone found in the blood and acts as a prohormone of the more active thyroid hormone, triiodothyronine (T3). Thyroxine and its acti ...

are higher than expected.

Thyroxine Thyroxine, also known as T4, is a hormone produced by the thyroid gland. It is the primary form of thyroid hormone found in the blood and acts as a prohormone of the more active thyroid hormone, triiodothyronine (T3). Thyroxine and its acti ...

or tetraiodothyronine (T4) is produced by the

thyroid gland The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans, it is a butterfly-shaped gland located in the neck below the Adam's apple. It consists of two connected lobes. The lower two thirds of the lobes are connected by ...

. The term is sometimes used to refer to

hyperthyroidism Hyperthyroidism is a endocrine disease in which the thyroid gland produces excessive amounts of thyroid hormones. Thyrotoxicosis is a condition that occurs due to elevated levels of thyroid hormones of any cause and therefore includes hyperth ...

, but hyperthyroidism is a more general term. When the level of

(T4) in the blood exceeds normal range, it can lead to symptoms such as irritability and unexplained weight loss. Types include: * Familial dysalbuminemic hyperthyroxinemia * Familial euthyroid hyperthyroxinemia * Thyroid hormone resistance syndrome

References

External links

Thyroid disease {{endocrine-disease-stub