At What dose does T3 downregulate Thyroid?

[jeffylyte]

Its back to everybodies favorite supplement. This one is perfect for Warlobo

Basically my question is this: At what dose of Cytomel (T3) does it start to shut down endogeneous thyroid production? Is there a threshold level? I remember seeing a reference that anything below 25mcg doesnt shut you down to an appreciable extent but I dont remember where. I know that therapeutic doses range from 5-50mcg. If you could include a reference.

And btw, Warlobo I did read your T3 link-of-links

 

[stealth]

t3

I use 23mg 4x'x a day. Because it works. Keep the cyle under 5 weeks and increase / decrease doseage slowly. It will create hypothyroid condition if you are not careful

 

[stealth]

opps typo 25mg 4 times a day

 

[duff_rose]

This is just from research, not experience...
It's a good idea to start at 25mcg and up it 25mcg per day until you reach 100mcg. Not a good idea to go above 100mcg per day because of permanant thyroid damage.
I would like to hear some oppinions from people who have done it first hand a few times though.

 

[jeffylyte]

ITs not thyroid damage that the quesition is about, but TSH and T4 production. They should downregulate in response to the increase in T3, but at what does does is start to become appreciable. For instance, everybody here knows to taper the T3 down if you are on 100mcgs. Why? cause of the rebound. The rebound is caused by the lack of TSH and therfore T4 and therefore T3 in the body due to supraphysiogic T3 from the cycle.


Another way of asking is for those hypothyroidics that take therapeutic T3 (forever mind you and they still dont get thyroid damge) do they have to worry about lowering (the already low) TSH and T4?