Thyroid UK
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Toxic with not converting T4

Hi all, I am struggling with crippling Hypo symptoms. I have been through a trial of Liothyronine and now I'm on Armour. On both trials I have had to take a ratio of 5:1 T4:T3 that is 5 times the amount T4 to T3. I have had a reverse T3 test which was in the high 30's proving I'm not converting T4, yet the only way I can get T3 is on the basis of taking T4 with it. I can feel and see that I am struggling again and I know it's down to T4. Does anyone have a similar experience of not being able to convert T4 and if so is anyone managing to get T3 prescribed without having to take the T4? On starting T3 I had a dramatic improvement in my symptoms but over time I feel such a significant decline again in my health that I can only believe its the failure to convert all the T4 I'm having to take. I am desperate, every day is a crippling misery and I would welcome any guidance anyone could give. Thank you.

4 Replies

Hi - you say you "had to take.." Why? Who is forcing you to take t4 in that ratio? You quite clearly have problems with it so why are you still taking it? If you really can't get t3 on prescription then why not consider self- medicating? T3 is actually quite cheap to buy outside uk so how much is your health worth to you?

Good luck xx


I wasnt converting T4 to T3 as have adrenal gland fatigue



Can you post your recent thyroid results and ranges?


I don't seem to convert enough T4 to T3 (based on blood and 24 h urine analyses), so I need additional T3 (I currently take Thai NDT brand Thyroid-S since neither Armour nor Erfa worked optimally for me). At one point, I tried to take T3 only, but felt terrible within one week. So, without knowing your medical history, I can say that I need T3 in addition to T4 but, although I seem to be a poor converter, I still need T4 along with T3. I cannot explain it, if it's not because T4 has a role on its own in the body (meaning its only role is not just to be converted to T3). On the other hand, some people only feel good on T3 only, which seems to contradict this theory...


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