How did you all figure out if you need more T4 ... - Thyroid UK

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How did you all figure out if you need more T4 or more T3?

Meanbeannyc profile image

I see people writing here, “if my FT3 was that low/high, FT4 that low/high, I’d feel very ill” etc.

I’m currently trying to find my combo replacement and wanted to know how everyone else figured out what FT4/FT3 level they feel well at.

My current labs 112 levo.

These are the best labs I’ve had since my thyroidectomy 14 months ago. Still feel like garbage. I feel the same as when my tsh was 7.

FT4 : 1.74 (0.78-2.19)

FT3: 2.56 (2.77-5.27)

TSH: 0.47 (0.47-4.68)

Endo advises 100/112 + 5 T3.

Or 112 + 5 T3

UPDATE: no one has answered my actual question as to how they figured out where they like their frees lol

48 Replies

Hello again, I only feel good on Levo when my T4 is over the reference range and that put my T3 at 70% in range. I probably could have used a tiny bit of T3 then but I functioned normally.

Your T3 is under the range. You're going to need a lot more than 5mcg. Looks like the amount of T4 you're on isn't high enough for any decent conversion. Have you taken a higher amount of Levo? I'd predict you'd probably need closer to 20-25 mcg of T3 with levels that low.

Meanbeannyc profile image
Meanbeannyc in reply to jrbarnes

20-25?!

I’ve never taken >112 levo, no.

jrbarnes profile image
jrbarnes in reply to Meanbeannyc

small increases or decreases in Levo have dramatic results for me. My T4 levels went down by 0.2 points and it resulted in my T3 numbers going down by 1.2 points. It was enough to take me from normal and functional to suffering. It's possible one or two increases in levo could really increase your T3 levels. If I had your percentage of T4 my T3 would be rock bottom.

Meanbeannyc profile image
Meanbeannyc in reply to jrbarnes

Do you know how much 25 T3 is?! lol

jrbarnes profile image
jrbarnes in reply to Meanbeannyc

thyroidpatients.ca/2019/09/...

This is a good article that shows 25mcg of T3 is not the usual replacement dose for people who don't have thyroids. Maintenance dose range from 50-125mcg of T3.

There's a book called Functional Approach to hypothyroidism by Dr Kenneth Blanchard. It can be purchased as an online google book as well. He outlines that you can jumpstart your T4 by adding an additional 12.5 to 25mcg of SYnthroid for three to four days so you'd take 125mcg for three to four days, then drop back to 112mcg except take 125mcg on MWF. He states that if you do it this way you'll feel better after a few weeks. It's an interesting approach but from what I read from his previous patients it was effective.

Meanbeannyc profile image
Meanbeannyc in reply to jrbarnes

I can’t keep up with you jrbarnes.

I asked at what level of frees does everyone feel well.

Not advice to take 50-125mcg T3. Which would be equivalent to almost 1000mcg T4.

that's why I said 20-25mcg of T3 because it looks like that dose of T4 isn't doing too much for you.

Meanbeannyc profile image
Meanbeannyc in reply to jrbarnes

What’s that mean

jrbarnes profile image
jrbarnes in reply to Meanbeannyc

personally I'd try to increase your Levo to 125 to see if your T3 levels rise.

Meanbeannyc profile image
Meanbeannyc in reply to jrbarnes

112 is a “big dose”For my weight

If you mean it's over 1.6 mcg per kg of bodyweight, remember that the 1.6 mcg thing is for a starter dose ... For many of us, where we end up is trial and error, with every change as a tiny baby step so you don't miss your personal "sweet spot".

I agree with other posters that you are very likely to need more than 5 mcg of lio per day - but 5mcg is a good starter dose. A lot of us are prescribed 20 mcg per day when we start lio - but it's best to build up to this slowly with 5 mcg a day for the first couple of weeks, then add another 5 mcg so you take two doses a day, several hours apart, stay like that for a couple of weeks, then add another 1/4 tablet etc until we're on a whole tablet, usually in two doses.

Once you're on a dose that feels right, hold for 6 - 8 weeks and re-test bloods. Many of us like our frees to be in the top 1/3 or higher of the reference range. Taking lio necessarily suppresses TSH so don't worry how low that goes. Over-range free T3 suggests you are over-medicated and might want to consider a dose reduction.

Good luck x

Yes over 1.6xkg. It’s 2.11xkg. I am approx 53-54kg

I’m not starting lio at 20mcg LOL

I know you're not starting there ... what I said was that a lot of us are initially prescribed this, but build up slowly to it, in 5 mcg increments, whilst agreeing with other posters that a total dose of 5 mcg isn't likely to touch the sides, given your results. You asked how other people titrated up to find their ideal dose - and I told you.

If you know you can't take more than 10 mcg of lio, I'm not sure why you asked ...

I asked where people felt good with their free levels.

jrbarnes profile image
jrbarnes in reply to Meanbeannyc

I weigh 47kg, have half a thyroid, and I'm on 88mcg but this week added an extra pill because brands are lower in potency than my old generics, so that's 704mcg of Levothyroxine per week. If I went by body weight that would put me at 75mcg but that would put my T4 at 40% or below and T3 at maybe 0-20% in range. If I move T4 up to 82% it puts my T3 under 40%. Push my T4 to 92% and my T4 enters the 40% range. If my T4 is 113% and over the range then my T3 is at 70%. 70% and above T3 is where I can finally start feeling normal.

When I experimented with natural desiccated I had to take all the way up to 120mg, which has 75mcg of T4 and 18mcg of T3. That just got my T3 into the 70% range and T4 in the 40% range. I had to take a lot of extra T3 to compensate for a 12mcg loss of T4. It's different for everyone because absorption and potency of brands can affect your T4 levels and conversion affects T3. Personally, I'd rather push my T4 to the point where I've got just enough to get my strength back and feel normal then top it up with a small amount of T3. I think this comes down to genetics. Some people will do better on mostly T4 and others will do better on more T3 and less T4. You can't drop your T4 to 100mcg without compensating with a lot of added T3.

Have you done one of those DNA tests and looked at your raw DNA and SNPs? There are certain SNPs that might give you a clue as to what therapy may work better for you.

What brand Levo are you taking?

Meanbeannyc profile image
Meanbeannyc in reply to jrbarnes

Synthroid brand name

jrbarnes profile image
jrbarnes in reply to Meanbeannyc

Do you have an option to try a different brand? Brands like Synthroid and Unithroid and even generics made me feel unwell due to the lactose, talc, povidone or acacia that they put in their pills. Many people feel unwell on Synthroid due to fillers. I had nausea, dizziness and burning in my fingers and I'd feel terrible all day. I go to a functional nurse practitioner and she says many people do well on brand name Levoxyl. I made the switch and those symptoms went away.

Meanbeannyc profile image
Meanbeannyc in reply to jrbarnes

Why would I try a different brand?

jrbarnes profile image
jrbarnes in reply to Meanbeannyc

Many people don't due well on Synthroid due to the inactive fillers. It's something you should be aware of. I had to try different brands due to side effects from fillers until I found Levoxyl and do much better on it.

Meanbeannyc profile image
Meanbeannyc in reply to jrbarnes

I haven’t felt any side effects that wouldn’t be due to poor hormone levels

Could it be that you feel like garbage cause your T3 is so low?

If more Levo doesn’t suit you then you’ve got to go down the route of adding T3 and 5mcg is a starter dose, you will probably end up needing much more.

Meanbeannyc profile image
Meanbeannyc in reply to NWA6

I did try titrating up my T3 a few months back and that didn’t make me feel much better either. I do feel better on 112 then I did on 88 and 100. Maybe slightly hyper-y jittery

NWA6 profile image
NWA6 in reply to Meanbeannyc

But your T3 is so low 😱 #complicated

Meanbeannyc profile image
Meanbeannyc in reply to NWA6

Right? Idk.

Meanbeannyc profile image
Meanbeannyc in reply to NWA6

I do like my 112 levo tho. Even tho I feel a bit amped. Better than being hypo lol

SlowDragon profile image
SlowDragonAdministrator

When we take levothyroxine plus T3 we START by adding 5mcg T3 in morning

See how that goes.....after a week or so ....likely to need to add 2nd 5mcg dose T3 mid-late afternoon

Stick on this for 6-8 weeks and retest thyroid levels

Essential to regularly retest vitamin D, folate, ferritin and B12 levels.

What vitamin supplements are you currently taking

Vitamins likely to be very low with such low Ft3 levels

Both levothyroxine and T3 need OPTIMAL vitamin levels

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

If/when also on T3, make sure to take last third or quarter of daily dose 8-12 hours prior to test, even if this means adjusting time or splitting of dose day before test

Re your test results--What are the units of measurement?

Meanbeannyc profile image
Meanbeannyc in reply to

Idk, why does that matter?

Good luck Meanbeannyc! I find it’s fascinating! How can these doctors ever think that one size fits all when we’ve got people like you who seem super sensitive to changes and people like me who seem to absorb it and gain super powers! Lol (ok slight exaggeration 😂 but after being hypo for so long ‘normal’ does feel superhuman 🤗)

Meanbeannyc profile image
Meanbeannyc in reply to NWA6

I don’t really know what normal feels like NWA :(

I’ve had hyperthyroidism since I was 24. Then got REALLY sick from carb after 10 years. Had a TT and haven’t had a tsh <6 in 15 months. This is the first time my labs have looked somewhat decent

NWA6 profile image
NWA6 in reply to Meanbeannyc

Bloody hell! I was on the sofa barely able to function when my T3 was 3.5 (3.5-6.5) when it went down to 2.5 I thought I’d loose my mind, I lived in a world that felt surreal.

Sorry I know virtually nothing about hyper even though my sister had it a couple of years before I was diagnosed hypo, we were a right pair when we got together, me on the sofa barely able to focus on the conversation while I watch her cook up a storm in the kitchen. She could never keep still. Quite irritating really! Lol I know she had an awful time though, she was so tired but couldn’t keep still 😬

Meanbeannyc profile image
Meanbeannyc in reply to NWA6

LOL. Well I feel pretty Effin bad. Both are bad. Hyper and hypo.

I function pretty well either way lol.

I just worked a 75 hour work week on my feet everyday on a 6 day stretch. So I have enough energy to do THAT.

My co worker has no thyroid and takes T3 only!!... and only takes 10mcg cytomel, tsh of 1.

She was on 350 levo post op with a tsh of 96.

Meanbeannyc profile image
Meanbeannyc in reply to NWA6

The very first day I went on 112 I felt better.

And the very first day I took cytomel I felt better.

So now I wanna combine 112 with 5 T3.

How did you all figure out if you need more T4 or more T3?

I have taken thyroid hormones for 7 years. I started on Levo but couldn't tolerate it at all, so I have spent most of my time on T3 or (briefly) NDT.

Earlier this year I started taking Levo for the first time in years, and for the first time ever I tolerated it.

When I got up to 75mcg per day my Free T4 was at a pretty good level, but my Free T3 was still too low for my liking.

So I decided to increase by 25mcg per day i.e. up to 100mcg. I knew this would probably take my Free T4 over the range but I wondered if it might raise my Free T3 as well.

I recently tested again after about 8 weeks on 100mcg per day. As I expected my Free T4 rose above range. But the surprise was my Free T3 - it hadn't risen at all. In fact it was a tiny smidgen lower than it had been at 75mcg Levo per day. But at least I found out an upper limit to my Levo dose.

I have now reverted to 75mcg Levo per day but have added 1/4 tablet of T3.

How’d u feel with FT4 over range

Not very good. Permanently very tired and yet I found it extremely hard to get to sleep. My memory is very poor and I actually felt as if I was suffering from dementia. I found it enormously difficult to keep a thought in my head for more than two seconds.

But since my Free T3 was actually very slightly worse on 100mcg Levo than on 75mcg I reduced my dose of Levo with no regrets.

jrbarnes profile image
jrbarnes in reply to humanbean

Interesting. This is something I'm experimenting with now. "The glass ceiling of T4 mono therapy" on thyroidpatients.ca describes your experience with Levo. Your labs prove there is a ceiling and by raising T4 levels it appears to be slowing down T4/T3 conversion. When on Levo only do you have a suppressed TSH below 1 ?

I only feel better with my FT4 levels over range but naturally have a higher TSH, still mid 1 range, despite higher T4 levels. I should note I have half a thyroid that wasn't able to put out enough T4 on its own. I suspect conversion isn't my issue but having enough T4 to get the job done is the culprit. I have the CC allele on SNP rs2235544 which indicates increased DIO1 activity and increased T3 levels.

I recently came across a study that showed "patients with DIO2 rs225014 (TT) and rs225015 (GG) variants have higher TSH levels, and should take higher L-T4 dose." After looking at my raw dna data found I have both of those. I was skeptical about using this information to solve my thyroid dilemma but my genes indicate I most likely do better with mostly T4 and a tad bit of T3.

humanbean profile image
humanbean in reply to jrbarnes

When on Levo only do you have a suppressed TSH below 1 ?

When I was on 75mcg Levo only my TSH was below 1 but was in range.

0.48 (0.27 - 4.2)

When I was on 100mcg Levo only my TSH was below range but not by much.

0.21 (0.27 - 4.2)

I definitely didn't feel good with Free T4 over the range. I found it hard to sleep and my heart rate was frequently high i.e. over 100 and sometimes as high as 130. I really don't want to get into the habit of taking beta blockers to slow my heart rate down. I'd prefer it if my heart would control itself naturally.

jrbarnes profile image
jrbarnes in reply to humanbean

Thanks. This is informative and evidence that it's not one size fits all.

humanbean profile image
humanbean in reply to jrbarnes

I do have some issues with my pituitary which could alter my TSH and thyroid related numbers. The pituitary has a stalk. Mine is stretched. The bulk of my pituitary is rather flattened although I've never been told I have "empty sella".

Before I started treating my thyroid my TSH never even got as high as 6. But my Free T4 was only 8% of the way through the range. On another test my Free T4 was 14% of the way through the range and my Free T3 was 11% of the way through the range.

I've seen people quoting levels of Free T4 and Free T3 that were similar to the ones I mention above, but in those cases the TSH was anywhere from 10 - 30. So, yes, nothing that is thyroid related is one size fits all.

I had to beg my doctor to prescribe Levo for the first time, and she did it very reluctantly. I'd first been told my thyroid was "borderline underactive" over 20 years before. Unfortunately there is only very limited evidence that I have autoimmune hypothyroidism. My thyroid never got dramatically worse, it just stayed poor, but not poor enough for anyone to decide I needed treatment for a few decades. I actually had a few symptoms suggestive of hypothyroidism when I was pre-school age.

jrbarnes profile image
jrbarnes in reply to humanbean

That's a condition I've never heard of and unusual to have such low free hormones without an extremely elevated TSH. To this day I don't know the cause of my hurthle cell adenoma as it occurs in less than 5% of cases ,usually in 70-80 year old women so they don't bother to research it more. I have very little evidence that it's autoimmune related. I too had symptoms as a child, which I look back on now as clearly being subclinical hypo. It started with cystic acne, then hypoglycemia and slight fatigue. It makes me ponder how long I was functioning in life with low T4 levels. I often joke, how can doctors say thyroid disease is so easy to treat when they can't diagnose symptoms in the first place and people must beg for treatment or wait until they have golf ball size growths? Reading different stories on this forum has opened my eyes to the wide range of thyroid disorders. Thanks again!

My FT3 is the best it’s ever been on 112. That’s why I wanted to stay on it

Thanks for actually answering my question, BEAN TO BEAN

You're welcome. 👍

I take Levo 100 mcg only so I can't answer your main question. The mess below basically says you're a poor converter of T4 toT3 but you already knew that. PS I used to live on the Lower East Side, now the fashionable East Village, before it became posh...

Behavioural parameters: your test results

TSH: 0.47 mU/l

FT4: 1.74* ng/dl

FT3: 2.56 pg/ml

Structural parameters: results thru the Spina Thyr app

GT: <Not computable>

GD: 16.24* nmol/s

sGD: -2.75*

TSHI: 2.3

sTSHI: -0.65

TTSI: 58*

Structural Parameter ranges

GD: 20 - 40 nmol/s (Conversion rate of T4 to T3)

TSHI: 1.3 - 4.1 (below range may indicate hypothalmus, pituitary malfunction)

TTSI: 100 - 150 (higher values may signal resistance to hormone)

The sGD and sTSHI are standard deviations from midpoint values -2.0 to +2.0 range

Meanbeannyc profile image
Meanbeannyc in reply to

The “mess”? LOL.

I grew up in the village too! I wonder if we know each other.

in reply to Meanbeannyc

I grew up upstate, waaay upstate north of syracuse and lived in Manhattan for a short time in the eighties. My wife lived at First and First for 8 years in a four story walk-up.

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