Under medicated: Hi I’m having a few problems... - Thyroid UK

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Under medicated

flo-jo100 profile image
19 Replies

Hi I’m having a few problems with my endo. I’m on NDT and the last 2 bloods tests were done late afternoon on meds. I began to feel undermedicated so insisted on getting my own bloods done first thing in the morning on no meds and there was a huge difference in my blood work. She raised my dose but doesn’t agree with me so we’ve come to a compromise I do my bloods my way but occasionally her way. Her reasoning is she needs to see how the meds are working! Do I look for a new endo?

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flo-jo100
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SeasideSusie profile image
SeasideSusieRemembering

flo-jo100

Do I look for a new endo?

Is your NDT prescribed? If not you don't really need an endo.

flo-jo100 profile image
flo-jo100 in reply to SeasideSusie

Yes it is

flo-jo100 profile image
flo-jo100 in reply to SeasideSusie

I am right in saying blood test needs to be done first thing in the morning on no meds aren’t I? She’s got me questioning myself now.

SeasideSusie profile image
SeasideSusieRemembering in reply to flo-jo100

flo-jo100

Yes, when booking thyroid tests, we should always book the very first appointment of the morning and fast overnight (water allowed) . This gives the highest possible TSH which is needed when looking for an increase in dose or to avoid a reduction. TSH is highest early morning and lowers throughout the day. It can also lower after eating. However, NDT can lower, even suppress TSH which your endo should know if prescribing it.

When taking NDT only there should be 8-12 hours between the last dose of NDT and blood draw. (If on Levo it would be 24 hours.) This is because of the T3 in NDT and the fact that T3 has a short half life. If you take your NDT any more than 12 hours before blood draw you will get a false low FT3 result, if you take it too close to the blood draw you will get a false high FT3.

These are patient to patient tips which we don't discuss with doctors or phlebotomists.

flo-jo100 profile image
flo-jo100 in reply to SeasideSusie

Thanks for your reply. I took my 2nd dose of NDT at around 1 pm my blood test was following morning at 8.30. These are my results

Tsh 2.89 0.27-4.20

T4 total L 48.0 66-181

Free t4 L9.06 12.0-22.0

Free t3 4.36 3.1-6.8

SeasideSusie profile image
SeasideSusieRemembering in reply to flo-jo100

flo-jo100

So your last dose of NDT was 19.5 hours before the blood draw. That gives a false low FT3. So we actually have no idea what your normal circulating FT3 is. We can guess that by adding 20% it would be around 5.2 but that is a very rough guess only. FT3 is usually best nearer the top of the range.

However, your TSH is far too hgh for a treated hypo patient, when on NDT it is usually very low or suppressed. FT4 is usually low as well.

She was right to raise your dose.

Dee8686 profile image
Dee8686 in reply to SeasideSusie

Tsh is far too high- should that read SeasideSusie ?

SeasideSusie profile image
SeasideSusieRemembering in reply to Dee8686

Oh yes, thanks Dee. I'll go and edit it.

greygoose profile image
greygoose

Her reasoning is she needs to see how the meds are working!

That's popycock. Testing after taking a dose doesn't show how the 'meds' are working. Just shows you how much of the dose you've previously taken that day is left in the blood. What does that prove? She's just trying to sound clever in order to get her own way.

flo-jo100 profile image
flo-jo100

So am I better next time taking morning dose 6am then around 2pm for blood test and leaving out 2nd dose which I usually have around lunchtime?

SeasideSusie profile image
SeasideSusieRemembering in reply to flo-jo100

flo-jo100

Yes if you have to have an afternoon blood test but that gives just 8 hours. The window is 8-12 hours, so no less than 8 hours. Then take the second dose after your blood test.

flo-jo100 profile image
flo-jo100 in reply to SeasideSusie

Ok will do thank you for all your help much appreciated.

flo-jo100 profile image
flo-jo100

Hi again how would I do it if I had an am blood test

SeasideSusie profile image
SeasideSusieRemembering in reply to flo-jo100

flo-jo100

You change the timing of your NDT so that your last dose is 8-12 hours before your blood test. So if your blood test was 8am then you would take your last dose of NDT no earlier than 8pm the evening before, and no later than midnight. I have to do this when I have a test because I take a combination of Levo and T3, so I just change the timing for that one day.

flo-jo100 profile image
flo-jo100 in reply to SeasideSusie

Ah ok got it! Thanks again!

SeasideSusie profile image
SeasideSusieRemembering in reply to flo-jo100

You're welcome :)

flo-jo100 profile image
flo-jo100 in reply to SeasideSusie

Does the t3 dose at night keep you awake?

SeasideSusie profile image
SeasideSusieRemembering in reply to flo-jo100

flo-jo100

I don't split my dose. When I first started taking T3 I took 1/4 tablet in the morning. When I added the second 1/4 I took it late afternoon, I've never taken it at night. But I got fed up of trying to time food and drink around taking the second dose so I started taking it all in one dose evenwhen I increased further. It didn't make any difference to how I felt so I just take an early morning dose now and don't have to worry about timing anything else.

flo-jo100 profile image
flo-jo100 in reply to SeasideSusie

Ok thanks again

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