THYROID HORMONE RESISTANCE-RT3
Dr Bronner Handwerger NMD
Thyroid resistance syndrome is a result of the body converting T4 (Thyroxine) to a form of T3 (liothyronine) know as reverse T3. This can occur on its own or if a person has been on T4 containing medication like Synthroid or even one of the porcine glandular medications such as Armour thyroid. As long as T4 is coming into the body there is the ability for it to be converted to reverse T3 if the correct conditions exist.
Reverse T3 is completely inactive. The body has a built in mechanism for the balance of T3 and RT3. Under various conditions the body can shift the ratio of T3 to reverse T3 and an imbalance can occur. You can calculate the ratio of FT3 to RT3. A healthy ratio is greater then 20.
What happens if I make too much RT3? It will become an issue. It binds to the T3 receptor sites. This in turn blocks the beneficial effects of T3 and the result is that you remain functionally hypothyroid and have many of the lingering symptoms even if your labs look normal. This can be very frustrating for many patients and they can suffer if this situation is not found and corrected. Many people who seem to chase their dosing of thyroid medication have thyroid resistance. The typical story I hear is I began on one dose and have had to continually increase the dosing because I feel good for a few weeks and then the symptoms return. This continual need for dose increases is a sure sign of thyroid resistance syndrome.