Thyroid UK
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Any advice please Underactive Thyroid Bloods done for regular Thyroid test raised TSH levels

I had been taking Eltroxin 75mcgs for 3 yrs and a few months ago started to feel ill, very agitated, couldnt sleep,palpitations, muscle pain and soreness and very hyperactive meds reduced to 50.

Now on Activa have been for 2wks now due to shortage of Eltroxin, thing is when they up my dosage my palpitations occur when they reduce it my TSH levels go up.

I do have an Arrythmia saw Cardiologist no medication needed, this started after i was placed on Thyroid meds, doc says its not connected i think it is.

Seeing Doc on Wednesday and want to go armed with plenty of info so i dont get fobbed off again, any help/ideas would be greatly appreciated.

Many thanks


3 Replies

Hi I suspect it may be linked to your FT3 level. A lot of NHS Labs will not longer test for this. For the correct treatment you need tSH, T4 and Free T3. FT3 plays a prominent part in heart conditions. Must be in range too. It is possible that the lesser T4 is best but that you also need some T3 too. You can only tell this with the 3 tests.I have 3 different sort of arrythmias , and my Labs never do FT3 now, For this reasons, and because my Endo and I consider it essential, I pay on line at Blue Horizon ( main site), quote TUK 10 for a £ 10 discount. With that , the 3 tests are about £61 for venous blood, for most people the finger prick, about £70 is more convenient. These are extremely reliable, a well know Lab and the one mostly used by the private hospitals. Then if you feel you need treatment, take these results + the given ranges to the doc.If this still s a problem ie theT4, then you may need armour or Erfa, however, although I am allergic to T4 , I have to have mine on a private script, I have a little T3 with it from GP. Whichever you do it is essential to have the 3 tests. My GP will not prescribe NDT but a few good GP`s will.

I hope that helps

Best wishes,


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Thank you so much jackie that info has heped so much.regards dotti


If you had been given Mercury Pharma Levothyroxine, then you would not have switched makes - it is exactly the same product as Eltroxin except for the packaging. See the news item on the main Thyroid UK web site:



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