Help with my latest thyroid results please

[Kit_Monster]

I have just had my TSH, T3 and T4 results back and I'd be really grateful of thoughts on what they could mean....

I have been on T4 meds for 6 weeks, with a change in brand, bit not dosage after 2 weeks due to side effects (nausea and headaches mostly) which have disappeared since the switch.

Test results - blood taken at 5.30am on 26/06/21 before daily T4 dose.

TSH 0.46 (0.27-4.2) so 4.83% through range. Prior to T4 meds 47%.

FT3 3.5 (3.1-6.8) so 10.81% through range. Prior to T4 meds 22%.

FT4 16.3 (12-22) so 43% through range. Prior to T4 meds 36%.

I expected the TSH to drop and the T4 to improve but not my T3 levels to effectively halve!! What is going on? And should I be worried?

I've got a consultation in about 2 weeks and I'd like to go in with some info already on what this could mean and next steps.

From the posts here from.all the lovely members on this forum, I know the 50mcg T4 is usually just a starting dose .

[tattybogle]

So part of the explanation is this which is known to happen;

Most T3 comes from conversion of T4 by the body , but some T3 is directly produced by the thyroid.

Before Levo , when your TSH was 2 ish .. your thyroid was being asked (by the TSH)to make a bit more T3 than 'usual' ~ a bit like a T3 'boost' switch..... then when 50mcg Levo is added, the TSH falls quite dramatically , and that signal to the thyroid to 'boost' it's T3 production is gone . so the T3 goes down .

This might not be the full explanation for your lower T3, as the rate of conversion from T4 to T3 by the body may also have changed because changes in TSH and fT4/ fT3 levels have an impact on conversion.

This is the trade off we make when we take Levo ... we get lower TSH ....relatively higher T4 , but relatively lower T3 .

You will probably have a hard time getting most GP/ Endo's to consider increasing Levo dose now that your TSH has fallen so close to the bottom of the range and fT4 is mid range.... you will need to get them to focus on the lower fT3 result, which they may be unwilling to look at.

But since they were obviously prepared to try you on levo with 'normal' TSH / fT4 / fT3 results , hopefully they will be open minded to considering your T3 level now .

[Kit_Monster in reply to tattybogle]

Hi tattybogle, thanks for your reply. So, if I understand it correctly, as well as losing the T3 that the thyroid produces, I might be a poor converter of T4 as well.

I ended up going to a private Dr because my GP just refused to accept that I was struggling because the TSH results were normal.

It will be interesting to see what the next steps will be at my up and coming appointment.

Thank you for helping me workout what might be going on....

[tattybogle in reply to Kit_Monster]

previous results No Levo ....TPOab / TGab negative

TSH: 1.4 [0.27 - 4.2]

FT4: 13.6 [12 - 22] 16%

]FT3: 3.96 [3.1 -6.8] 23%

~~~~~

No Levo

TSH:1.94 (0.27 - 4.20 ]

TT4: 75.8 (66 - 181)

FT4: 14.0 (12.0 - 22.0 ) 20%

FT3: 4.48 (3.1 - 6.8) 37%

~~~~~~

"After a 2 month trial of dual hormone HRT to see if that influenced my thyroid at all, my results came back as follows:

TSH: 2.12 ( 0.27 - 4.2)

FT4: 15.6 ( 12 - 22) 36%

FT3: 3.9 (3.1 - 6.8) 21.6%

Bloods taken before 9am, not T4/T3 medicated

Dr agreed that my thyroid is still struggling and decided to prescribe Teva T4 at a 50mg starting dose.

(The Dr thinks I may have poor T4 -T3 conversion, so this really is a trial on the T4 to see if it will make a difference or not.)"

~~~~~~~~~~~~

6 weeks on 50mcg Levo ... taken at 5.30am before T4 dose.

TSH 0.46 (0.27-4.2)

FT4 16.3 (12-22) 43% (Prior to T4 meds 36%)

FT3 3.5 (3.1-6.8) 10.81% . (Prior to T4 meds 22%)

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

So i don't think you could say your 'conversion' was poor when you were not on levo , .. because both fT4 and fT3 were lowish on both those tests . .. so rather than 'poor conversion', that just looked like 'not enough T4' , and T3 was at that point still doing relatively well.

However as fT4 has increased ,fT3 has got significantly lower .

So poor conversion could turn out to be an issue for you ,yes .... but at the moment it's hard to know for sure how much of this drop is from the thyroid now making less T3 and how much is from conversion of T4 being poor.

If your Levo dose is now increased to increase your T4 level, and your T3 doesn't get much better then yes, 'poor conversion' is a reasonable conclusion .

[Kit_Monster in reply to tattybogle]

Ah I see. - can't conclusively say I am a poor converter yet.

I've been wracking my brains to try and work out what was different back when my T3 was at 37 %. I don't have any vitamin / mineral results from around that time,... I wish I'd kept a detailed diary of diet etc.

Thanks again for helping 😊

[tattybogle in reply to Kit_Monster]

The difference between the fT3 on test 1 and test 2 (and the fT4 differences too ) are actually relatively small ...... in reality you could get that much difference between fT3 tests done at a different time on the same day , or if did some exercise , or if you rested etc . so i wouldn't pin too much on it. But yes diaries are a good idea . i wish i had much better records of 'what i did /when' and how i felt at the time.