T3 ratios: Hi is there a a rule of thumb for the... - Thyroid UK

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T3 ratios

afonog profile image
18 Replies

Hi

is there a a rule of thumb for the above. I've just read that it's 5:1 and a post from an admin that said 3:1.

I am hypo and have two sisters with the same condition. Both my sisters a re doing well on T3 combo. I'm going to docs on Tuesday to insist on an endo appt but am totally unable to get T3 at the moment so have ordered online from Cyprus and am going to self medicate. Currently on 100mcg of thyroxine and feel rubbish. All the normal, brain fog, tired, weight gain etc etc. will get a copy of my previous bloods on Tuesday and post here, although apparently they'll be a waste of time as I have never stopped my meds before a blood test so can only assume this will have impacted all my results for the last 15 years!!

Any info gratefully received.

Thank you to Sulamaye for her help.

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afonog
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18 Replies
QUE6T-33 profile image
QUE6T-33

Hi there - I'm being dumb, but what do you mean by T3 Ratios ?

shaws profile image
shawsAdministrator in reply to QUE6T-33

It means that if you are taking a combined T4 plus T3. It is 3 parts of T4 to 1 part of T3, e.g. if your T3 is 25mcg the equivalent T4 is 75mcg.

ncbi.nlm.nih.gov/pubmed/204...

If we take 20mcg of T3 the nearest T4 would have to be 50 instead of 60mcg as it would be difficult to cut a tablet to equal 60mcg.

QUE6T-33 profile image
QUE6T-33 in reply to shaws

Hi Shaw. What would be equivalent T3 dose to one grain

Armour ?

shaws profile image
shawsAdministrator in reply to QUE6T-33

Approx 25mcg of T3 to 1 grain NDT.

shaws profile image
shawsAdministrator

If you are taking a combined T4 plus T3. It is 3 parts of T4 to 1 part of T3, e.g. if your T3 is 25mcg the equivalent T4 is 75mcg.

ncbi.nlm.nih.gov/pubmed/204...

If we take 20mcg of T3 the nearest T4 would have to be 50 instead of 60mcg as it would be difficult to cut a tablet to equal 60mcg.

QUE6T-33 profile image
QUE6T-33

Hi Shaws - your a gem for that. Thanks - helpful.

Clutter profile image
Clutter

Afonog, T3 is 3 x stronger than Levothyroxine (T4) ie 25mcg T3 is equivalent to 75mcg T4.

ncbi.nlm.nih.gov/pubmed/204...

tpauk.com/images/docs/reduc...

If you post your results with the lab ref ranges members will advise whether you need to reduce your T4 dose when you add T3. You should start with a quarter tablet (6.25mcg) for a week to see how you tolerate it before increasing to 12.5mcg in two split doses and have a blood test 6-8 weeks later to check FT3 before increasing further.

in reply to Clutter

Clutter

Should a short break (say four days?) be taken from T4 in order to eliminate the extra not required before the introduction of a reduced dose of T4 accompanied with T3?

I ask as when first introducing NAX, this was Dr P's protocol with T4.

Flower007

Clutter profile image
Clutter in reply to

Flower, no it's not necessary. T3 is either added as a dose increase or added to a reduced dose of T4. I think Dr.P's protocol is to take the strain off adrenals while adrenal support is added.

afonog profile image
afonog

Thank you very much. I'll get all my results on Tuesday and post them here from previous tests. I'll get the new ones ASAP and won't make their take of taking thyroxine before the tests this time.

This site is amazing!

greygoose profile image
greygoose in reply to afonog

Afonog, you should leave a 24 hour gap between last dose and test. Also, get the blood taken as early in the morning as possible - between 8 and 9 - or even earlier if possible. And Don't have your breakfast before the test, either, as that will lower the TSH.

You know, people talk about the ratio of T4 to T3, and T3 being x times stronger than T4, but if you can't convert that T4 you're taking, it isn't equal to any T3 at all. These statistics are just guides, and as we're all so different in the way our bodies handle things, we have to be prepared to be flexible, and not think these things are set in stone. You might need more T3 than this, or you might need less. We have to adapt to our own needs, not what others think these needs should be. :)

afonog profile image
afonog in reply to greygoose

Earliest our doc does bloods is 10am!! I shall go easy on the t3 to start and see how I feel. My go is going to throw a fit but hey ho. You'd think she would be more supportibpve as she has an over active thyroid.

greygoose profile image
greygoose in reply to afonog

Blimey! Here in France, the labs stop taking blood at 10.30, because after that, it's too late. Well, I just hope she realises that the TSH is going to be lower at that time than it would at 8.00. But you still mustn't take your thyroxine before the test - and if you can skip breakfast - have a slap up brunch afterwards - that would be better.

Clutter profile image
Clutter in reply to afonog

Afonog, use the orange Reply button to respond and the member will be sent email and on-site notifications that you have replied.

afonog profile image
afonog

Oops , that should have said make the mistake..........

Jacs profile image
Jacs

I began self-medicating t3 /t4 combo for some time, and wonder if someone can jog my memory on what happens to T4 and tsh as a result?

I recently had call from doc after blood test which showed tsh of 22+ and t4 of under 3; I had recently cut down a lot on T4 because I felt better. as doc warned I was in danger of getting mxydema I have started to take more t4 but to be honest feel awful - return of real exhaustion. I'm confused!

Clutter profile image
Clutter in reply to Jacs

Jacs, your TSH rose to 22 and your FT4 dropped <3 because you were undermedicated. If you reduced or stopped T4 you should have increased T3 dose to compensate. People on sufficient T3 only will generally see low/suppressed TSH, low (possibly below range FT4) and high in range FT3. On T4+T3 TSH is usually low/suppressed, FT4 low to mid range and FT3 in the top third of range.

QUE6T-33 profile image
QUE6T-33

Hi Shaw - thanks reply. Yes, that's what I thought.

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