Thanks to some great people on here, I've been taking T3 for about 10 months and Its definitely made a difference. Can't say its helped weight loss or anything, but generally feel much better overall.
Im interested in why a lot of people say to reduce T4 when starting T3. Im currently on 112.5mg of T4 and use 6mg of T3 (quarter of a pill) along with it in the morning.
Would it be worth reducing the T4 to 100mg? Just wondered what the theory was behind reducing the T4.
Thanks
Depends on your test results. Many people reduce T4 to prevent over dosing if the T4 is high in range.
Most people on Levo only will have got their FT4 fairly high in range before adding in T3.
On combination therapy most people aim for both FT4 & FT3 being around 70%. So if the FT4 is much above 70% then that person will need to reduce to avoid over replacement.
hello Ooohmatron I guess I wondered why you want to change your dose? 112.5 T4 and 5 or 6mcg T3 sounds like something an endo would prescribe. Unless you have symptoms or you have test results that suggest you are over or under that doesn’t sound like a very unusual amount of T4 to me. I’m an 80kg male with not much thyroid tissue left. I take 100 T4 and 15 T3 and feel pretty ok on that - took quite a bit of trial and error to get there. Like other posters suggest, maybe be guided by your symptoms and aim for T4 in range and T3 towards the top of the range. Good luck.
Thanks for the info. Yes my Dr describes me the T4 but I added the T3 (which my Dr knows about) about a year ago. Im a big guy, about 120kg and Ive been on 112.5mg of T4 for a while now and my numbers were middle of the range with that, but found my T3 was pretty much near the bottom end of the T3 level, which is why I added it. Initially I took 25mg of T3 a day, but then found my levels went just over the top end. Now i take a quarter of a table so roughly 5/6mg a day but I'm wondering if it should be slightly higher again, not 25mg, but maybe something in between. I get regular bloods done, but its so tricky trying to find that balance.
Do you take your 15m split up throughout the day or all at once?
T3 is approximate to 4 x thyroxine so you can roughly work out total T4. Not sure how you take 6 mcg T3 as a quarter tablet. The highest T3 I know is 20 mcg not 24?.?
I was on 125 mcg T4 but dropped this to 100 when introduced T3 but only 5 mcg daily but as this was equivalent to 120 mcg daily I still felt a tad under treated so added 25 mcg T4 3 times a week and now feel I’ve got it right.
Its a quarter of a tablet Im taking, so it will be around 5/6mg, basically its not half or a whole tablet.
I don't feel a quarter is high enough though. I was on 25mg a day to start with but that pushed my T3 level over too much, so scaled it back. Im actually beginning to wonder if I need it somewhere in the middle.
How do you take your 25mg x3 a week?
Also, do you do blood tests and if so, do you measure them before taking the T3 or after?
cheers
I am sure it would be good to see your most recent blood test results. Depending on where your FT4 levels are it’s very hypothetical. I take a relatively low dose of Levo and my FT4 is scraping the very top of the range and most importantly it’s not helping me feel better.
High FT4 and low FT3 not a good combination.
Just the other day, I finally had a consultation with an endo. He said that pushing the FT4 levels higher, can inhibit natural FT3 production. Crikey if I have heard that before, I have definitely overlooked it. I was so stunned I did not ask for the ‘science’. He added “the body just won’t always do it”. I assume some sort of protective mechanism (RT3?).
So maybe in some patients this is what is happening. I have to say I have always understood, or at least thought that FT4 levels had to be quite high to begin to feel better, especially if introducing T3.
I have now reduced my Levo with a view to his strategy. He (in my case) wants to reduce my Levo and introduce T3. Placebo effect or no, I have been feeling better already!
Thanks for taking time to reply, I know what you mean about getting levels right, its a minefield.
I was on T4 (112.5mgs) for years, and felt ok, but never seemed to have much energy. Levels were
TSH : 1.77
Free T3: 3.8
Free Thyrx: 20
With my T3 being low, I then added T3 and as mad as it sounds, started on 50mgs a day. I was taking 25mgs in the morning and 25mgs in the afternoon. Readings after this went
TSH : 0.124
Free T3: 8.5
Free Thyrx: 15.6
Naturally, I then reduced the T3 to 12mgs a day (half a tablet split into 2 doses, morning and afternoon). Readings after this were:
TSH : 0.79
Free T3: 3.9
Free Thyrx: 12.3
As it stands, I probably don't need to reduce my T4 from 112.5mg, as the readings don't seem particularly high for TSH and Free Thyrx. However, my T3 is much lower again and Ive noticed weight gain etc. I know 50mgs was too high, but boy did I feel energised and losing weight did work when I applied exercise/good diet.
All other factors, Vitamins etc, Im on top of.
I have always wondered why so many people insist on reducing T4 when starting T3, although I understand the worries about overdosing T4.
But in my experience of taking both T4 and T3, when T3 is added to my T4 dose my T4 reduces by itself.
One factor must be that I still have a thyroid which, when left to its own devices, still produces some T4, but it just isn't enough. (I doubt 8% of the way through the range is enough for many people.) I suspect that either my thyroid reduces my own T4 output as a response to the extra T3, or it simply isn't capable of producing more T4.
Another factor might be that I think I have Secondary Hypothyroidism because my pituitary doesn't work well and is completely flat. I've been told it was probably like that since I was born. This could have meant that my pituitary was never able to stimulate my T4 production enough. My thyroid may have atrophied over my lifetime as a result of too little TSH.
But this is all conjecture. I haven't been officially diagnosed with Secondary Hypothyroidism, only Subclinical Hypothyroidism which my doctor tried to convince me didn't need treating.
The other thing to (perhaps) take into consideration seems to be that everything does not seem to be converted by the thyroid itself, or be able to be observed in the blood tests. Blood tests may still be a rudimentary guess (but the best we have as yet). Again we are back to what goes on elsewhere. We know that conversion takes place in peripheral areas but the science as yet can’t measure it. Only what’s floating around ‘free’ in the blood. The TH may well be at ‘normal’ levels in the blood but much of T3 used up very quickly by the brain and heart leaving little for other activity (I think).
Well your FT4 levels have dropped just like is highlighted on the Forum, when introducing T3. That was very brave of you taking such high amounts of T3 at introduction. Still you seem to have learned something from that!
Sounds like you might have T3 from Greece at 25mcgs tablets. So a quarter is 6.25 mcg. It’s difficult to increase by a small amount, as even 6.25 mcgs is difficult to get accurately BUT it’s possible to cut 6.25 mcgs into approximately 3.13 mcgs. It’s fiddly but worth it. The medical profession are shocked but I just brazened it out with “Needs must”. So it’s a way of increasing your T3 nice and gently. There is an old saying in medicine “less is more” so just increase by small amounts. You are looking for a ‘sweet spot’ not starting from scratch!.
Yes I have been fiddling around with my FT4 levels for a while because introducing T3 for me was a nightmare. A private endo (18 months ago, could be longer) told me “levo is not going to help you and you can’t take T3”. Then she refused to treat me further!! Basically I felt like I had been given a terminal diagnosis.
I know it’s early days, only reducing my Levo but for the first time in a while no SVT, so it may be that the combination of the high FT4 level plus the intro of T3 without reducing the Levo has been my problem. I know endos more often than not want Levo reduced when introducing T3, which does not seem to be, dare I say, the message I often see on the Forum. However just maybe, this is what it is, in my case.
Anyway I am now willing to try something, anything that sounds like a strategy - and off course, hopefully getting my T3 paid for by theNHS, where we in the U.K. should be getting it!
I have as yet only reduced my Levo. No T3 introduced yet. I am awaiting his direction.
Should I reduce T4 or T3 
Advice re blood sample and when to take T3. T4
T4/T3 combo reducing Levo
