Originally posted 2013-04-27 07:16:13. Republished by Blog Post Promoter Hyperthyroidism is a metabolic imbalance that causes overproduction of thyroid hormones. The thyroid gland is this little butterfly-shaped organ behind the larynx that produces thyroid hormones; thyroxine (T4) and triiodothyronine (T3), responsible for certain metabolic processes such as energy metabolism, temperature regulation, and other sympathetic activities in the...