As a clinical nutritionist and consultant to many well respected Dr, I have found chasing Rt3 in several cases ended up in failed attempts. In some cases cause more issues. The approach which has worked the best was to find out why your rt3 was high then address it from there. Rt3 is raised by the body for a reason to protect it self. In many cases of rt3 I have dealt with the main reason rt3 was elevated was stress from either the imbalances in the neurology, biology, environmental, nutritional, or genetic factors. All of of these areas need to be explored before IMO putting a person on t3 only. I personally chased Rt3 for years, feeling good then feeling worse never stabilizing. It was not until I goto to the root of the problem did I finally make advances in my health and well being. Just simple nutritional factors where able to resolve many cases, or just healing the GI tract and cleaning out the liver properly. If you are on t4 only, I would look into factors to why t4 was not converting. Then may be suggest 5-10 mcgs BID to help bridge till the main problem was found. Bloods are just a diagnostic tool when most of the real happening its at the intracellular and mitochondial level. One needs to look past the serum. Dr refer cases when all the numbers in blood are fine, cortisol, ferritin, hormones are in check but they can not figure out where else to look. After a while this becomes not only a science, but an art form…

@hypoman 5357 wrote:

Dr. Mariano,

I had read in a prior thread on this forum that you prefer to see total T3 @ 330 to 420 pg/dL and total T4 @ 8.0 to 12.0 ug/dL [ http://www.definitivemind.com/forums/showthread.php?t=575&highlight=levothyroxine ].

I have been using T3 monotherapy as a means to reduce rT3 and TSH to desirable levels. Is there really any reason to add separate T4 in the case of a depressed free and total T4?

In addition to its main function as a storage hormone whose job is to convert to T3, specifically what metabolic or other functions does T4 have? Does it really matter if both T4 levels are depressed as long as one is getting enough T3? I was warned that my T4 level would bottom out as a result of taking T3.

In addition, SHBG has been driving up. Could this also be due to T3 as I have read?

In any case, I have never tried T4 before and thought this was a prime time to give it a shot and add 50mcg/day to the 100mcg T3. My biggest fear is that I run the risk of driving rt3 back up which is why I stuck with T3 only, especially if I have a conversion block or other inflammatory issue preventing T4 to T3 conversion. In this case, I would be reversing the goal of the T3 monotherapy.

While natural dessicated products like Armour are T3-dominant, I have read that such do not produce the same problem with increased rT3. Is this something you’ve observed as well?

Bottom line is whether adding T4 is worth the risk of increased rT3. Do you think keeping the T3 in place will help prevent that?