Does an infection or virus reduce FT3 levels. - Thyroid UK

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Does an infection or virus reduce FT3 levels.

lucylocks profile image
14 Replies

I read somewhere yesterday that infections and viruses can reduce FT3 levels.

I tried to find the information again today but cannot find it, I should have saved I know.

Does anyone know if this is the case and if so does anyone have a link to it.

Thank you.

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lucylocks
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warchile profile image
warchile

Chronic illness , infections and virus's can cause the body to slow the metabolism and hoard bodily resources.

The general effect is to change the behaviour of the thyroid and the production of various hormones.I'm not a medical professional so I can't go into specifics about the mechanisms.

Chronic illness and autoimmune conditions therefore can produce long term slowing of the metabolism which is the core effect of hypothyroidism.

On that basis , it can be beneficial to treat and underlying illness before trying to deal with hypo symptoms that may arise.

lucylocks profile image
lucylocks in reply to warchile

Thank you warchile,

the reason I ask is I have had what I thought was a virus and my FT3 has dropped from 5.2 to 3.5, I have had a raise in my antibodies, but they are still in range, but just under top of the range. A member said I may have had a hashi' flare so do not know if it is in fact a flare and caused me to feel ill or it is a virus and this in turn had reduced my T3 level.

warchile profile image
warchile in reply to lucylocks

My experience is that a short term virus should not meaningfully affect T3 levels.

I am not a Doctor , this is important to bear in mind.

This is why all forum posters need to post their full results as one measure (like T3 level) doesn't really give any indication of what's really going on.

Variations can also be caused by day and time of the test , what medications you have taken and how much time has passed since last taking medication.

Its also more difficult if taking T3 medication as it has a short life in the blood stream.

Usually the best indication is how you feel , if you're feeling unwell after a few days it could be the virus. If your levels are consistently down after further tests then its likely there's something else at play.

lucylocks profile image
lucylocks in reply to warchile

Thank you.

Here are my recent results.

I take 1.5 grains W.P. Thyroid one grain am. and half grain early evening.

Bloods taken 12 hours after last NDT dose and I fasted.

TSH 1.06 range 0.27 - 4.20

Total T4 47.9 range 59.0 - 154.0

FT4 9.74 range 12.00 - 22.00

FT3 3.58 range 3.10 - 6.80 - level was 5.2 range 3.8 - 6.0 in February, 17 hours after NDT

TPO antibodies 95.77 range 0 - 115.00

TPA antibodies 32.02 range 0 - 34 - this has risen from 27.5 in August 2015

warchile profile image
warchile

I am not an expert in reading results but the fact that you're under range in T4 and low in range in T3 suggests you may have had an anomalous result last time.

To me you latest results look to be sensible. You may need to look at rebalancing your dosage.

It doesn't look like its virus inspired to me but I'm not an expert.

Hopefully one of the real experts will be along to give you advice on what to do next ....

If nobody comes along be prepared to repost with your full results.

greygoose profile image
greygoose

If you have a virus, and your body needs to conserve energy, you convert less T4 to T3, and more T4 to rT3. That is why your FT3 level drops. Sorry, I don't have a link.

Oh, and when you have the autoimmune disease, Hashi's, the immune system destroys the thyroid, that's why your thyroid makes less hormone, because there's less of it. :)

PS, a virus will not lower the T3 you've taken in NDT. And, presumably, you started taking T3 because you were a bad converter, anyway. What I said above applies mainly to people on T4 only, and non-hypo people.

lucylocks profile image
lucylocks in reply to greygoose

Thanks greygoose,

I'm still not sure why my T3 has dropped so much, whether virus or hashi's or anything else for that matter, just know I feel c__p

greygoose profile image
greygoose in reply to lucylocks

No, and you'll probably never know. But, it's more likely to be the Hashi's than anything else. But, if you feel bad, you need an increase dose, that's all.

lucylocks profile image
lucylocks in reply to greygoose

greygoose do you believe that someone can have hashi's even if there antibodies are in range, as mine are.

Both are near to top of the range and the TPA have risen

TPO antibodies 95.77 range 0 - 115.00

TPA antibodies 32.02 range 0 - 34 this has risen from 27.5 in August 2015

Thank you.

greygoose profile image
greygoose in reply to lucylocks

It's perfectly possible. :)

lucylocks profile image
lucylocks in reply to greygoose

Thanks greygoose, so I would be better cutting gluten out then.

greygoose profile image
greygoose in reply to lucylocks

At least give it a try. See if you feel better. Try it for about three months, then try eating gluten again, and see if you notice the difference. It works for a lot of people.

lucylocks profile image
lucylocks in reply to greygoose

Thank you, yes it is worth giving it a try.

Best wishes.

greygoose profile image
greygoose in reply to lucylocks

:)

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