RT Book, Section A1 Idrose, Alzamani Mohammad A2 Tintinalli, Judith E. A2 Stapczynski, J. Stephan A2 Ma, O. John A2 Yealy, Donald M. A2 Meckler, Garth D. A2 Cline, David M. SR Print(0) ID 1132929147 T1 Hyperthyroidism T2 Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 8e YR 2016 FD 2016 PB McGraw-Hill Education PP New York, NY SN 9780071794763 LK accessemergencymedicine.mhmedical.com/content.aspx?aid=1132929147 RD 2024/03/29 AB Thyroid hormone affects all organ systems and is responsible for increasing metabolic rate, heart rate, and ventricle contractility, as well as muscle and central nervous system excitability. Two major types of thyroid hormones are thyroxine and triiodothyronine. Thyroxine is the major form of thyroid hormone. The ratio of thyroxine to triiodothyronine released in the blood is 20:1. Peripherally, thyroxine is converted to the active triiodothyronine, which is three to four times more potent than thyroxine.