About a month ago I decided it was time to try T3 again. I've done all I can to improve the conversion of thyroid hormone by taking supplements to bring up vitamins and minerals, however I'm still taking iron supplements since my ferritin and serum iron took a dive in March due to my persistently low thyroid hormone levels causing heavy monthly cycles. Also, I've been paying more attention to getting enough food despite a low appetite. This has improved my conversion on T4 alone but despite all that it's still not raising my FT3 levels enough and each time I attempt to increase the T4 beyond 50 -60% in range I start to get this pain in my neck and body, cracky bones, and terrible brain fog to the point I can't comprehend a sentence.
I've been alternating days on 112mcg and 100mcg with an added 5mcg of T3(daily.) On Aug 13th labs showed my FT4 was 50% in range and FT3 is 48%. I took the T3 about 13 hours prior to testing and T4 at 24 hours. Always fasting. Last week I moved up to 10 mcg of T3, which has helped.
For several years on T4 only I always had top or over range FT4 but also had near top of range FT3 and felt normal except for some lingering hypo symptoms. Only since 2016 have I become unable to tolerate high FT4 levels and perhaps it's only because my FT3 levels dropped so significantly. I only seem to be able to tolerate high FT4 when the FT3 is high as well. Every time I attempt to raise my FT4 levels back up to 90% in range like in the past I get these debilitating symptoms. So I've decided to keep my FT4 around 50-60% in range and slowly increase my T3. Has anyone found that they need to keep the FT4 lower around this range? It's boggling that when I lower my Levo all of a sudden my mind is clearer and I can think properly. I have no choice here but to increase the T3.
One of the most positive effects of taking the T3 is that I've been able to regain some of my singing voice that I lost 13 years ago after going on Levothyroxine. It's making my skin look so much brighter and healthier and I feel some water bloat coming off.
Apologies because I know there's probably been so many posts about this and I've sifted through a lot of them. Thanks for any replies.
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jrbarnes
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TSH stimulates production of thyroid hormone (in a healthy gland) but it is a group of enzymes called deiodinases that determine activation/deactivation of thyroid hormone, eg whether the thyroid hormone will bind to the nuclear receptor in the cells, etc. This local control allows the cell to adjust the amount of thyroid hormone based on the body’s needs at any given time, and because the deiodinases create active hormone through differing mechanisms it ensure a reliable supply.
Deiodinases are influenced by factors such as genetic make up, life style & environmental factors, other health conditions, etc. However, they are also influenced by the amount & ratio of T4 & T3 in our blood, and there is a point individually set for all of us (our sweet spot) that when exceeded will make deiodinases/thyroid hormones start working against us. All this is why our labs are not truly reflective of what is happening on a cellular level.
Medicating thyroid hormone is tricky because we only know our sweet spot when we hit it and it may remain disguised behind other conditions until they are sorted (iron & nutrients deficiencies or elevated inflammation being prime examples). When we know these influencing factors have been addressed we can assess more realistically levels/ratios. I too only have both sets of thyroid hormone around 50-60%, with FT3 sometimes a little higher than FT4. This is where I function best and rarely test any more.
Many forum members can’t convert enough T3 with Levothyroxine mono-therapy without exceeding their T4 sweet spot, and this risks the deiodinase enzymes altering behaviours to start converting more inactive metabolites in an effort to protect the body. Therefore, excess T4 will be turned to RT3 whilst T3 will congruently convert to an inactive form of T2 (no matter what T3 levels are), and so loss is felt in both hormones and we may become symptomatic.
These negative enzyme behaviours are reversible when excessive thyroid hormone taken above our sweet spot is reduced, but duration of excess and other health conditions will determine speed of recovery. Brain fog is a classic symptom of excess T4. Remember FT4 levels do not have to be top of range or over-range to be deemed excessive. Excessive is where the medicated amount is more than our bodies can deal with positively, and so in an effort to protect it will start converting to inactive metabolites.
You sound as if you are one of the many with a genuine need of a little T3 meds. Often adding a little T3 will up-regulate enzymes to convert further T3, and so we end up with more than the amount we medicated even in the total absence of a thyroid gland. I hope your recovery continues.
Thank you for the informative reply. Mid range T4 seems to be where most are comfortable and I feel like I'm on the right track. Just getting used the the idea that I don't need to have top of the range T4.
This is a reply helpful and thorough reply. Thank you. It has helped me to understand what I observed when an increase in levo took my T4 was right at the top of the range and my t3 started to drop a reduction in levo helped. I wonder if you have an insight on where I am now?
I have started T3/T4 combined now and I think I have the opposite problem and my T4 is too low at 18% through the range with T3 at 65%.
I expected finally getting my T3 above the 40-50% mark would resolved my symptoms and I'd feel great but instead I'm feeling really hypo, very fatigued, brain fog, headaches, constipation and bloating. Is it because T4 is too low now? What's the ideal ratio or is it different for everyone?
I’ve recently found that I feel better with mid range FT4 and high FT3. I think it’s very much trial and error to see what works best for you. I have to increase/ decrease medication super slowly (eg 12.5mcg Levo or 2.5mcg Lio alternate days for several weeks) and am definitely more of a tortoise than a hare when it comes to adjusting!
I’m delighted to hear about you singing again and having improvements to your skin and water retention issues.
I was concerned that I was keeping my T4 too low after years of having high T4 but it's reassuring to know that others are able to keep the T4 a little lower with added T3. I also have to do increases very slowly.
My doses result in my ft4 at 50% and my ft3 at 72% . Been on these doses for 14 months and I still feel improvement as my body heals in the longer term.
Have you tried splitting your levo dose so taking it 2 or 3 times daily? There is an idea that this may help conversion in some folks. When ft4 reaches a certain level in an individual, the body starts to convert t4 into reverse t3. This is a safeguard to stop us having too high a level of ft3. The thought is that for some folks the spike produced in FT4 by taking their daily dose in one go gets their ft4 level temporarily high enough to trigger some rt3 production. By taking levo in 2 doses their ft4 levels never spike high enough to trigger rt3 and so conversion improves.
The last time I felt well enough my FT3 levels were also around the 70-80% range. I've been giving a lot of consideration to splitting my T4 dose since I'm currently alternating with the 100mcg dose and I could simply ask my Dr to prescribe 50mcg x 2 daily. I'd have to split my 112mcg but I think it's the 112mcg dose that gives me the issue when taking all at once. 100 mcg isn't enough yet 112mcg is too much so I'm somewhere in between. When I trialed NDT for a year I always split my dose to 2 times a day. I'm definitely going to give it more thought. I may ask the Dr for the 50mcg pills and perhaps 25mcg so I can split those and add it onto the 50s.
Some of us just do not tolerate T4, myself included!
I only seem to be able to tolerate high FT4 when the FT3 is high as well.
I think you're rather putting the cart before the horse here!!
The significant thing is the FT3 level rather than the FT4
You needed that higher level of T4 to produce adequate T3 by conversion
Some people do need FT4 very close to the top of ref range to obtain a sufficient FT3....in order to achieve well-being
Some of us need to add T3 to achieve this
As you know T3 is the active thyroid hormone which, for good health, needs to saturate almost every cell in the body. It is required in a constant and adequate supply.
You now appear to be experiencing the benefits of adding T3. When I was wrongly medicated my voice became husky and very croaky, my then GP considered referring me to ENT....she didn't realise low T3 was the problem. Adequately dosed this resolved....wish it had also given me a singing voice!!!!
Don't apologise....it sounds as if you are doing well..
Hi, thanks for the reply. You're right about the T3. Even though I was on Levo and my FT3 was 70-80% in range I still had hypo symptoms like that husky voice and was sent to an ENT where they put a scope down my nose to look at my vocals then sent me to do a barium swallow test. My endo even suggested that I could go ahead and have the other half of my thyroid removed! I know people who tell me they don't have issues with taking Levothyroxine alone but then they tell me how tired they are and other health issues they have. I've never met anyone that takes T4 alone and tells me they feel good. It seems that being on T4 only will keep most people in some kind of state of hypothyroidism. Up until 2016 I could get top level T3 levels with high T4 but not anymore and I wonder if at some point the other half of my thyroid gland stopped producing hormone which may have contributed to those higher levels. All I know is that I have to give up on that high T4 route because it doesn't work anymore. Thanks again
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