Blood test: Hi I’ve got a lot of brain fog and... - Thyroid UK

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Blood test

flo-jo100 profile image
11 Replies

Hi I’ve got a lot of brain fog and several other symptoms at the moment I completely forgot to space my NDT doses out the day before my blood test🙄 how will that affect my t3 reading?

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flo-jo100 profile image
flo-jo100
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11 Replies
SeasideSusie profile image
SeasideSusieRemembering

Possibly will show a low FT3. How much T3 did you take and how many hours before your test?

flo-jo100 profile image
flo-jo100 in reply toSeasideSusie

I took 1 grain the morning before and 3/4 around lunchtime usually the lunchtime dose I would take around 10pm in the evening. So it was 20 hours

SeasideSusie profile image
SeasideSusieRemembering in reply toflo-jo100

In that case then I strongly suspect the FT3 result will be a false low. Take that into account when interpreting the results.

flo-jo100 profile image
flo-jo100 in reply toSeasideSusie

Thankyou. I have a lot of hypo symptoms but I will take that into consideration.

SeasideSusie profile image
SeasideSusieRemembering in reply toflo-jo100

If you have hypo symptoms it sounds like you may be undermedicated.

flo-jo100 profile image
flo-jo100 in reply toSeasideSusie

Yes I feel it. I had parasites and Candida so had to get rid of all that which changed things and I went over medicated so had to drop down but I think now will have to raise back up again. Thank you

flo-jo100 profile image
flo-jo100 in reply toSeasideSusie

Hello I just received my blood test results very low

T4 10.1 (12.3-20.2)

T3 4.2 (3.70-6.70

My previous blood test in March was

T4 14.7

T3 6.4

I was getting bad headaches so was told to reduce from 2 grains to 1 3/4 which I did. It seems a huge drop even with messing up the last blood test. I have increased by a 1/4 grain would appreciate your thoughts.

SeasideSusie profile image
SeasideSusieRemembering in reply toflo-jo100

Obviously there is room to increase your dose, so stick with your 1/4 grain increase and retest in 6-8 weeks to see how things are going.

flo-jo100 profile image
flo-jo100 in reply toSeasideSusie

Thank you will do

jamesal0 profile image
jamesal0

Hi FloJo - why would you alter your NDT dose the day before bloods? Yes don't take them the morning of your test. But unless you run a TSH=0 and were worried about what the GP might think. I wouldn't change anything.

flo-jo100 profile image
flo-jo100 in reply tojamesal0

Sorry I meant to say alter the time of my last dose

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