<unk> <unk>  T3, or<unk>  is a molecule which is an isomer of<unk>  (T3). It is derived from thyroxine (T4) through the use of deiodinase.<unk> , unlike T3, does not stimulate thyroid hormone receptors. However,<unk>  nonetheless binds to these receptors, thereby blocking the action of T3. Under stress conditions, the adrenal glands produce excess amounts of cortisol. Cortisol inhibits the conversion of T4 to T3, thus shunting T4 conversion from T3 towards<unk> . Consequently, there is a widespread shutdown in T3 binding across the body. This condition is termed<unk>  T3 Dominance.  It results in reduced body temperature, which slows the action of many enzymes, leading to a clinical syndrome, Multiple Enzyme Dysfunction, which produces the effects seen in hypothyroidism. Effects include: fatigue, headache, migraine, PMS, irritability, fluid retention, anxiety and panic.
Reverse triiodothyronine
Parathyroid hormone 
Estradiol 
Dehydroepiandrosterone
Calcitonin 
Calcitriol 
Testolactone
Cosyntropin