Is my High ft3 causing symptoms or a lower ft4 ... - Thyroid UK

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Is my High ft3 causing symptoms or a lower ft4 that I'm not used to??

ThyroidObsessed profile image
49 Replies

Latest results

FT3 - 7.06 (3.1-6.8)

FT4 - 15 (11-23)

TSH - 0.45 (0.27- 4.5)

On 100mcg Levo and 10mcg T3.

On Levo only my results were -

FT4 - 24 (11- 23)

FT3 - 4 (3.1- 6.8)

TSH - 6 (0.27- 4.5)

HELP SUFFERING MENTALLY DEPRESSION AND ANXIETY HELL!!!! 😭😭

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ThyroidObsessed
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49 Replies
SlowDragon profile image
SlowDragonAdministrator

How long was last dose of T3 before blood test? Should be 8-12 hours

Same question for levothyroxine - should be 24 hours

Assuming they were these time gap

Personally I would increase levothyroxine by 12.5mcg per day and retest in 6 weeks

Do you split your T3?

2 x 5mcg? What time gap?

ThyroidObsessed profile image
ThyroidObsessed in reply toSlowDragon

No I always take my tablets after the blood draw...

Iv not felt any better mentally at all since starting T3 😢...

I feel like i did when i was undermedicated on levo alone!...

I just don't get how that can make sense when technically I have increased my dose altogether as i didn't lower my Levo t all I just added in 10mcg t3 to it..

Yes I take 5 t3 with my Levo in a morning and the other 5 in the evening...

I'm thinking because the ft3 is over range that maybe I need to lower my Levo slightly to alternate days of 75- 100 to get the ft3 down a bit??

All I know is I'm an anxious nervous wreck with my ft3 this high!!

SlowDragon profile image
SlowDragonAdministrator in reply toThyroidObsessed

So what time was last dose of T3 before blood test?

FT4 result is very near bottom of range. Really don’t think you want to lower levothyroxine

If anything, you need small levothyroxine dose increase

ThyroidObsessed profile image
ThyroidObsessed in reply toSlowDragon

About 14 hours....

I'm not sure about increasing Levo as when I increased before from 75 to 100 iv felt worse!!

I really think it's the over range ft3 that's doing this, hence why I think decreasing levo slightly will help lower the ft3 a tiny bit?

ThyroidObsessed profile image
ThyroidObsessed in reply toSlowDragon

Also I thought the ft4 didn't matter when on t3 as our body's need t3 not t4... what about the people on t3 only their ft4 is below range??

SlowDragon profile image
SlowDragonAdministrator in reply toThyroidObsessed

Every person is different

Many of us find low FT4 (despite high FT3) causes symptoms

Have you had saliva cortisol and DHEA levels tested?

ThyroidObsessed profile image
ThyroidObsessed in reply toSlowDragon

But people on t3 alone have a very low below range ft4 which says to me we don't need t4 at all!?

SeasideSusie profile image
SeasideSusieRemembering in reply toThyroidObsessed

ThyroidObsessed

But people on t3 alone have a very low below range ft4 which says to me we don't need t4 at all!?

We are all different. We cannot go by what suits anyone else.

I take a combination of Levo and T3. After almost 2 years of tweaking doses, I have found that my optimal results are FT4 and FT3 both about 75% through range. I have had my FT4 down as low as 8% through it's range when taking Levo plus T3 and I was very unwell, it took a whole year for my FT4 to build back up again to where I felt well when it got up to 75%.

If you haven't had cortisol/DHEA tested I'd do that, adrenals and thyroid are both part of the endocrine system so if adrenals are shot then thyroid hormone wont work properly.

in reply toThyroidObsessed

I second what SeasideSusie says. This is a very fine tuning. I personally felt terrible with ft3 close to top of my range, when ft4 was low (hypo/hyper symptoms), then with ultra high ft4 and lower ft3 felt very hypo, but not as anxious, just felt more like myself, but quite hypo in other ways. When both ft3 ft4 are high in range I get overdose symptoms, while others don't. So I figured I need both ft3 ft4 somewhere above mid-range, but not as high as 80%. Anxiety for me is either from ft3 too high, but also had anxiety and breathlessness when I recently lowered Levo from 150 to 125. If you drop Levo to lower t3 not sure how you might feel, I personally don't do well on low ft4, but some people do. It is easier to drop t3 because of it's half life, so very quickly you can see if this is causing anxiety. But again,everyone is different. It took me 2 years to figure out where I should be and so far it looks like 125 t4 and 10-12.5 t3 probably, but I'm not there yet. Oh, also bear in mind there are studies confirming that t4 is needed for direct impact on our brain cells so it's not exactly inactive, but some people require less and I honestly think it does have correlation with age and naturally hormones decline a bit when you're older , I feel mentally more stable on a decent t4 dose, anything around 90-100mcg makes me feel like I'm losing my mind to a degree! :)

ThyroidObsessed profile image
ThyroidObsessed in reply to

Thanks this makes sense... I'm thinking now of decreasing my t3 very slightly and see how I feel also gonna skip tonight's dose...

It's so weird as in the mid morning/afternoon I seem to go through hell mentally tearful and depressed then around 3-4 I'm ok again, even when I take my 4 o clock t3 dose I'm still ok....

in reply toThyroidObsessed

I used to be tearful in the evening when my levels were low of t4, but midrange t3...since your t3 is high enough, it would be strange if t3 is causing it, but the only way to find out is to try something first and asses. Unless you need ultra high doses of t3, some people do. Also some report then need low t4 to feel good on t3.. I only realised this when I went on Levo only and so many symptoms improved, especially mental ones. So I figured I need a higher dose of t4 than in Nature Throid and lower t3 than Nature Throid too x

Angel_of_the_North profile image
Angel_of_the_North in reply toThyroidObsessed

I feel better taking T3 3 or 4 times a day, but my free T3 is lower in range than yours

SlowDragon profile image
SlowDragonAdministrator in reply toThyroidObsessed

When someone is on only T3 they would needcto be taking much higher dose than 10mcg.....a full daily dose of T3 alone is usually somewhere between 40mcg and 60mcg

When on Levothyroxine plus SMALL split dose of T3, (as you are) many people find their FT4 drops when T3 is added, and that Levothyroxine needs small increase to improve levels

Obviously it's experimental, what suits you

beh1 profile image
beh1

I’m on levothyroxine and liothyronine and my t4 level is lower than yours, at 14, and my t3 around 5.5. What I do a couple of times a week is drop my second liothyronine dose, especially in summer, and this makes me feel better and has a quick impact on anxiety. If you lift levothyroxine dose you could well find t3 level goes even higher. Mine has in the past when I tried to raise my t4 level. Just my take on it. Everybody’s body is different.

ThyroidObsessed profile image
ThyroidObsessed in reply tobeh1

Yes this is what I have said before to people, iv increased my Levo from 75 to 100 and I'm worse!, I don't think this high level of ft3 suits me, I'm tearful depressed and anxious...

I know it's just gonna take time to find the right levels that suit me it's hard bloody work... it took me 2 years to convince my nhs endo to trial me on t3..

Iv been very lucky so need this to work out! 😭😭

HIFL profile image
HIFL

If it were me, I would try lowering the T3; maybe split the 5 mcg pill and take 2.5 mcg T3 twice a day. Keep the levo at 100 mcg for now. T3 stimulates conversion of T4 to T3, and the excess T3 may be causing your anxiety. Too high levels will also lower your cortisol, which could also cause problems.

The brain runs primarily off of T4, so I wouldn't want to reduce your T4, especially when it's your T3 that's over range. There's a lot of info on the brain's use of T4 and T3 here: tiredthyroid.com/rt3-7.html, but the main point is that too much T3 can cause memory and other issues (hyperthyroid dementia).

ThyroidObsessed profile image
ThyroidObsessed in reply toHIFL

Thank you I am thinking of doing this...

So I'm currently on 100mcg of Levo and 10mcg of t3 a day,do u mean I should drop down to 5mcg of t3 a day is that not too big a drop?

HIFL profile image
HIFL in reply toThyroidObsessed

Yes, 5 mcg T3 total daily. Given that you are having symptoms of overmedication, and that your lab results confirm T3 is too high, it seems you should reduce your T3. If you wanted to do it more gradually, you could try 7.5 mcg daily, as 5 mcg in the morning and 2.5 mcg in the evening, but that still seems like a lot, for you. You could try 7.5 mcg T3 first, then see how you feel before deciding whether to lower it to 5 mcg.

ThyroidObsessed profile image
ThyroidObsessed in reply toHIFL

Also just to add when on 100mcg of Levo alone according to my tsh I was undermedicated, weirdly my ft4 was slightly over range but my tsh was at 8!! Also my ft3 was not even mid range!!...

HIFL profile image
HIFL in reply toThyroidObsessed

Right, and this was why adding T3 made sense. I think you just took too much T3! Lowering your T3 dose should put everything in range. T4 should rise (due to less conversion to T3), T3 should fall (due to your taking less), and TSH should rise (because you lowered your T3 dose). Your lab results should end up in-between the two that you first posted.

NWA6 profile image
NWA6 in reply toHIFL

That doesn’t make sense? The brain doesn’t ‘run primarily off T4’? I thought low T3 meant that the brain was the last to get any because it’s needed to keep the body alive.

in reply toNWA6

Hey Paula, it actually does - you can see my response to HughH below, people have discussed it here several times. Hope this helps :)

HughH profile image
HughH in reply toHIFL

The brain runs primarily off of T4

T4 is not an active hormone - it is a storage form and needs converted to T3 to become active. Therefore the brain cells cannot run off T4.

in reply toHughH

Cheng SY, Leonard JL, Davis PJ. Molecular aspects of thyroid hormone actions. Endocr Rev. 2010 Apr;31(2):139-70. Epub 2010 Jan 5. ncbi.nlm.nih.gov/pubmed/200...

T4 in an unconverted state has direct impact on brain :) also T3 is needed by brain via conversion and/or direct ingestion if required

There is another one here: journal.frontiersin.org/art...

Also Diogenes has written recently on the forum here that t4 has a direct impact on brain..hope this helps! :)

NWA6 profile image
NWA6 in reply to

Thanks cupofca. I’ll have to take time to read your links. But I still can’t get my head around T4 ‘running the brain’ that’s not directly true is it! It still needs to convert. Never mind for now. I’m thinking out loud!! Lol Give me time to read and then question!! Lol

in reply toNWA6

No worries Lol :) this is just an interesting read. I felt a relief in my psychological symptoms from taking t4 so for me it works, but it might not be the case for everyone. T4 works in a brain I'm both states - converted and unconverted according to papers. But! Everyone is different, there are people getting by by taking t3 only! :)

NWA6 profile image
NWA6 in reply toNWA6

Nope! I still can’t understand!! Lol I’m sorry it’s just too confusing. I tried so hard on T4. No matter how much I took it never really raised much but once I got it to 22! (12-24) but my t3 never ever raised to 4, it usually sat around 3.5 (3.5-6.5) So for me what you’re saying just doesn’t register. T4 kept me alive but only that. Since adding t3 I am truly living life. But even now it only sits at 4.8 and my T4 is 16, which is ‘normal’ for me. For some they’d still not feel well with those low scores but for me, I’m so content 🤗

SlowDragon profile image
SlowDragonAdministrator in reply toNWA6

NWA6

You haven't been on T3 long ....

Like you initially I found just adding T3 was brilliant, (Levothyroxine was dropped down from 100mcg from 125mcg) .....but at each retest FT4 dropped a bit further. By 3rd retest (about 7 months in) FT4 was bear bottom of range and too low for me .......and causing symptoms (despite high FT3)

Suggest you keep an eye on your FT4 levels at each test

NWA6 profile image
NWA6 in reply toSlowDragon

Yes, that’s true Slowdragon. But I’ve also absorbed T3 much better than most that I hear about on this forum, 15mcg from day 1 without reducing my 175/150 per day with no repercussions of that whatsoever. I’ve also increased my T3 to 20mcg per day because I still had a couple of left over symptoms and my blood test showed that my T3 has only risen to 4.8 (I’d have expected more increase) I’ll test again before I go see the Doc in July because I’ve increased and it will be interesting to see my FT4 score.

Angel_of_the_North profile image
Angel_of_the_North in reply toNWA6

I find that every now and then (maybe once a month) I feel bad and then I take some NDT as well. On the occasions when I've done a blood test at the same time as feeling bad, my free t4 has been under range, so I suppose the NDT just boosts it into the bottom of the range. But everyone is different.

SlowDragon profile image
SlowDragonAdministrator in reply toNWA6

Ok - I thought your Levothyroxine was reduced to 125/150 when T3 was added

NWA6 profile image
NWA6 in reply toSlowDragon

Yes, but no reduction before adding T3. It was just one week 150/175 and then next week 125/150 plus 15mcg T3. Nothing introduced slowly. I feel like a sponge! Lol I’ll definitely take onboard what you’ve said and watch out for any symptoms that creep in. I just don’t feel like I’m sensitive at all. I wonder how much T3 I would actual have to take to feel a) over medicated or b) raise my FT3 to the top end. I find it all so fascinating but I’m counting my blessings atm that I’ve had no trouble introducing and that I’ve found something that works.

SlowDragon profile image
SlowDragonAdministrator in reply toNWA6

Ok so you did have Levothyroxine reduced.

Yes I simply reduced Levothyroxine and added T3 in, though I did it slower than you.

Initially dropped 12.5mcg Levothyroxine and added 2 x 2.5mcg T3, Then after week dropped another 12.5mcg and upped T3 to 2 x 5mcg.

After 6 weeks blood test, endo increased T3 to 20mcg daily. No further reduction in Levothyroxine. T3 as 3 split doses per day (10mcg, 5mcg and 5mcg, 8 hours apart)

Bloods retested 8 weeks later

At next blood test, which ididvas was feeling a bit "off", (so about 6-7 months after initial dropping of Levothyroxine from 125mcg to 100mcg) ..FT3 very good, near top of range but FT4 was down to fourteen and started to get returning symptoms

Tweaked Levothyroxine back up. Initially to 112mcg. Retested. Stopped dropping, but not increased. So increased back to 125mcg

Been on this ever since

Obviously I am vastly more active, on T4/T3 combo. Leading normal active life. Minimum 10,000 steps a day. Resting pulse about 55

Without T3 virtually housebound

HughH profile image
HughH in reply to

Thanks for your reply and the links. There seems to be conflicting information on this so it is confusing. There are many people, especially with thyroid hormone resistance, who take high doses of T3, so will have very low Free T4 levels, who do not seem to have any brain issues.

in reply toHughH

Totally! It is confusing, there are people on t3 only doing perfectly well! It was not the case for me, I needed t4 to balance me psychologically and gave me more clarity. There are too many factors to consider and why someone might take more advantage of one hormone over another. I just think it's important to outline that both statements are correct. Personally, I suffered a lot because I have been taking NDT and my ft3 was excellent, ft4 low, and it made me feel terrible, especially with anxiety, brain fog etc. Ft4 higher in range made me feel balanced so it's important we say it to people here who might benefit from it :)

HIFL profile image
HIFL in reply toHughH

have very low Free T4 levels, who do not seem to have any brain issues

I'm assuming you're talking about the people on forums who take only T3 and say they're fine. Yes, they breathe, their heart beats, etc., but has anyone tested their cognitive function? Have you conversed in person with someone who only takes T3? I haven't. The two things I noticed when I took too much T3 were memory issues and a short fuse, or being easily angered. T3 stimulates the brain and T4 calms it down.

T4 is not an active hormone - it is a storage form and needs converted to T4 to become active.

This is not a true statement. T4 has effects as T4. It's referred to as a non-genomic effect. Here's a list of studies from google: scholar.google.com/scholar?...

You also wrote T4 converts to T4. Are you taking too much T3? jk!

HughH profile image
HughH in reply toHIFL

My area of interest is thyroid hormone resistance and the treatment developed by Dr John Lowe was to take high doses of T3 only. He successfully treated a large number of patients.

Personally I know a number of people on T3 only treatment, all with great success. In some of them the short fuse is if they run out of T3 or forget to take it - they are much calmer when taking their T3 only.

I think that there is confusion at times between Free T3 levels and metabolic state. The most important thing is to get the metabolic rate correct - normal heart rate, basal temperature etc. To achieve this some people need large amounts of T3 causing very high Free T3 levels, but this is not harmful if their metabolic rate is normal.

I did mistakenly write "T4 converts to T4" it should have been to T3 and I have corrected the post.

HIFL profile image
HIFL in reply toHughH

Can I ask, are you on T3-only? You say you know people on T3-only; have you spoken to them in person, face-to-face, and not just through posts/email?

I agree that metabolic state and FT3 often don't correlate. Even more so for FT4!

FancyPants54 profile image
FancyPants54 in reply toHIFL

I think this is a terrible generalisation for those on T3 only. Yes, I've talked to Paul Robinson regularly over the past few years. Both online and on the phone. And he's as sharp as a tack, analytical and bright and has written not one but three very well put together books on T3 only, adrenal issues with T3 and on hypothyroidism in general. He has no thyroid left, it's been long gone for years and he can't tolerate any T4. He's an active sportsman and he does it all on T3 only and nutrients.

I have also had a lot to do with the admins who helped him run his patient forum. They were the same. Plus quite a few of the patients on it.

Many people swear by T3 only for getting their lives back. Don't knock it. It doesn't suit everyone by any means. But for some it's a life saver.

SlowDragon profile image
SlowDragonAdministrator in reply to

This seems really interesting research.....I certainly find I need good levels of BOTH FT4 AND FT3

I have Hashimoto's, Heterozygous DIO2 and gluten intolerant

in reply toSlowDragon

In total agreement with you SlowDragon, I'm the same! Hope you're doing well!

ThyroidObsessed profile image
ThyroidObsessed

Hey im the original poster 🙋‍♀️... it seems we all have different opinions on the matter at hand...

As my ft3 is over range and my ft4 normal and tsh normal, it makes sense to me to reduce my T3 and see if I feel any better mentally, i.e depression/anxiety/ brain fog...

Also I think I may have rushed weening myself onto T3 as I went from 2.5 to 10mcg in the space of only 2 weeks! Because obviously I wanted to feel better more quickly...

SlowDragon profile image
SlowDragonAdministrator in reply toThyroidObsessed

Yes that increase in T3 may have been too quick for you

Suggest you cut back T3 cautiously. Perhaps cut down by just 2.5mcg initially to 7.5mcg per day

5mcg in morning and 2.5mcg in afternoon

You might try 3 doses per day of 2.5mcg (yes it's speck of dust)

HughH profile image
HughH in reply toThyroidObsessed

Sometimes it is difficult to tell if you are under or overmedicated as the symptoms can be similar. You may need your Free T3 to be high.

Simple signs of overmedication are high heart rate and your hands will shake if you hold them out in front of you. Another way to tell is your basal temperature, taken before getting out of bed in the morning. If low you are undermedicated, if high overmedicated.

NWA6 profile image
NWA6 in reply toThyroidObsessed

I’ve been looking at your post these last couple of days and trying to decipher what I would do if I were in your shoes. It’s a quandary. But here’s my tuppence, not that it’s worth much as I’m a newbie, I’m going on gut here.

You don’t say you have any symptoms of overmedication, fast heart rate, extra beats, sweating, loose(r) bowels, shaking hands, insomnia. So I just wonder if you added another 5mcg what would happen? 10mcg is not much, is it too borderline a dose? Leaving you in nowhere land between Hypo/Hyper.

The other alternative is to up your Levo dose. So I would either leave my T3 at 10mcg plus 100/125mcg Levo (alternate days initially) or I’d take 15mcg T3 and leave my Levo at 100mcg per day.

I just don’t think I would reduce.

ThyroidObsessed profile image
ThyroidObsessed in reply toNWA6

Iv been on this rollercoaster for 2 years now so have got to know my symptoms well in correlation to my levels...

I was ok for 12 years on levo alone then boom 2 years ago I had some sort of mental nervous breakdown, levels were tested to reveal a slightly over range ft4 and just below mid range ft3 and a tsh of 8!, clearly showing I have conversion issues...

Iv fought for 2 years to get t3 from My NHS endo, so need this to work out!..

My symptoms seem to be of low ft4 I don't think my brain can function correctly with mid range ft4, so I am going to reduce t3 to 5mcg a day and stay on 100 Levo which if I'm correct will then increase the ft4 level and reduce the ft3 which is what i think I need...

I'll give it 6 weeks and see how I am...

Though 6 weeks seems forever away feeling like I do mentally!!! 😭😭

NWA6 profile image
NWA6 in reply toThyroidObsessed

Oh Lord 6wks IS a long time. But we all know we cant f**k about with our dosing willynilly 😩 I do find it amazing that we’re all so different. I don’t think I do well with a raised FT4 score. I’ve been moaning about symptoms for 10yrs, I’ve been atbtje docs 2/3/4 times a year telling her I don’t feel great and every other time my tests came back in range and so she tested for other things. Finally she got fed up with me and said it must be Fibromyalgia or the last time she said my symptoms sounded like menopause. I would just get really irate with her. 10yrs is a long time to be living a half life and trying to raise 4young kids. But all good now on my combo mix. I’m taking double your dose of T3 and my last result was only 4.8 (3.5-6.5) I guess I’m just a really crappy convertor.

I really hope you find the right balance that suits you. I can really empathise with how frustrating it must be and we have to be so patient, it’s just so damn hard. I’m sending you some cyber Irish Luck ☘️🤗

ThyroidObsessed profile image
ThyroidObsessed in reply toNWA6

Bloody hell 4 kids bless u, it will be even harder for u than the average hypo person then!...

The past few days gave been hell I seem to be worse when I'm on my period, so I have decided to go back on the contraceptive pill, as my anxiety is so bad around my period...

I get this like crazy feeling fusty almost painful head when my ft4 is too low it makes me feel like I'm gonna go crazy at any minute! I know not many on here can relate to my symptoms ad they are mainly mental.. u see i don't suffer physically like alot of u poor people on here I'm also very slim which is contrary of hypo... but the mental hell is horrendous...

I just want to be normal again as I'm sure u do...

But it's never a quick fix with hormones us it!!! 😭😭

NWA6 profile image
NWA6 in reply toThyroidObsessed

Yeah we had all of them within 5yrs and I was in bed at 6pm every night 😬 Good job hubby and I are equal partners in this family business 😉

I can relate to the mental symptoms. It’s hard to describe right? I think mine was a mixture of what it may feel like to be depressed, numbness- like I can say the emotion but not feel it. Irrational, omg I’ve been so irrational sometimes. I became phobic of phonecalls, I couldn’t have the phone near my ear, so I’d take all calls (if I had to) on speaker.

I’m now bigger than I’ve ever been, but I’m still only a size 12, 5ft 8, so I always got the feeling that my GP didn’t believe that my Thyriod was at fault. Also fabulous thick Irish hair, no brittles nails, I can’t remember ever having a cold. My symptoms were my own and unique to me.

I just wish you could have the same success that I’ve had with T3. I hope you keep in touch and let me know how you’re coming along. I know the mental anguish, it’s debilitating. My mental health was worse than my physical symptoms. I just thought that that’s who I was, broken 😔

Loads of best wishes and an overdose of Irish luck, you are going to find the right balance for you ☘️

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