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Hyper, bloods results, what happens now?

Hello all

Recently diagnosed Hyper (Graves) 6 weeks ago.

TSH <0.01

T4 51

After 3 weeks on Carbi (40mg) T4 went down to 42

Another 2-3 weeks later (today!) on a reduced Carbi dose (20mg) T4 is 20! Within range.

TSH is still dead.


Its only been 5 weeks, has this happened fast???? My Endo (who I haven't seen yet) told me I would take months to get back into range with such a high T4. She said at least 4-6 months for most....

My doc says to stay on 20mg for another 4 weeks and review? Really?? I understand I need to get lower for TSH to kick in (hopefully)... But since I have bad rashes and hives, I would've thought reducing a little wouldn't hurt now?

Any advice GREATLY appreciated :-)

5 Replies


You seem to have responded quickly to Carbimazole but FT4 is high in range and very likely to rise if you reduce dose too quickly.

It can take months for TSH to recover and some hyperthyroid patients find TSH never recovers. Most hyperthyroid patients are prescribed Carbimazole for 9-18 months to regulate thyroid before weaning off and trying for remission.


I am not a medical professional and this information is not intended to be a substitute for medical guidance from your own doctor. Please check with your personal physician before applying any of these suggestions.


Thanks Clutter... Yes, initially my aim is to lower from 20mg to 15mg... Mainly for some relief from my allergy to it...

Interestingly, when I started at 40mg, after 3 weeks allergy got really bad (A&E)... my levels had dropped 9 points only... Endo said it was ok to stay on 20mg (as this is what I had done on my own)... rashes virtual disappeared until 10 days ago, slowly creeping in, getting worse and worse... my levels are down 20 points in 2 weeks.... It almost makes sense that as my levels are coming down my body is telling me when Carbi dose is too high?!

Obviously this is guess work! And I am not a doctor! However, it feels like this...

Hmmm thanks for advice... 18 months seems like a long time to stay on a drug without attempting remission... but i guess everyone is different...

Many thanks




If the allergy gets worse ask your endo about Propylthiouracil (PTU) which is an alternative anti-thyroid drug.


Thanks Clutter

They have told me they rather I continue on Carbi if possible because as PTU is apparently worse for the liver. I am more inclined to think that its because it costs more?!!



PTU is a second choice drug because it can raise liver enzymes. Pregnant women are switched to PTU as it doesn't cross the placenta and people who don't tolerate Carbimazole may do better on PTU.


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