why doctors dont predcribe Cytomel only?

[florida7879]

Hi
can somebody explain me. Why someone who is hypothyroid with low T4 and also T3 and with poor conversion into T3 is not suplemented with Cytomel only? If T3 is an active form do we need T4 ( synthroid) at all if there is poor conversion of course?

[florida7879]

hi,
make sense, i agree i feel better when im on both . some people can feel better on cytomel only if their thyroid produce sufficient amount of hormone to function normaly. Everybody are different.

[goolarra]

I agree...T3 is very fast acting and out of your system quickly if not used.  If your FT4 levels is too low, you will not have anything available for conversion (even though you convert SLOWLY, you do convert some) as your T3 wears off or during peak demand periods.

You are correct that T3 is the only form of the thyroid hormones that our cells can use.  However, a  proper balance of FT3 to FT4 is necessary to keep hypo symptoms at bay.  Our thyroids, when working correctly produce much more T4 than T3...I guess maybe Mother Nature knew what she was doing, and we're just trying to replicate that with meds.    

[Red_Star]

I'd say you would feel hypothyroid quite quickly if you didn't keep taking your T3 within a certain time frame due to the short half life. If you only were on T3 only you have bypass the T4 to T3 conversion issues.

[florida7879]

what effect it would have if im only on T3 (cytomel) and my T4 are so low? in other words if my T3 would be ok due cytomel and T4 deficiency. Are there any side effect of T4 defficiency?

[Red_Star]

There are blogs and books on those who have successfully treated their thyroid condition with T3 only. You do need to know what you are doing however as T3 is 4 times more powerful with a short half life (some state 4 - 8 hours up to 1 day) compared to the T4 half life of 5 - 7 days.  More commonly a smaller dosage of T3 added to existing T4.