The physiological actions of thyroid hormones are generated predominantly by T3, the majority of which (around 80%) is derived from T4 by deiodination in peripheral tissues. Synthetic T4 is identical in chemical framework on the T4 manufactured while in the human thyroid gland. Levothyroxine sodium has the molecular formulation C15H10I4NNaO4· https://cicill197bik4.cosmicwiki.com/user