hi all,
I have always benefitted from a higher up the range T4. However, I have been reading recently that this is now considered dangerous and I should aim for 50% through the range. Just wondered what you all thought about this, and what range do you consider safer? Thank you
Within range is ok, many need to be around 70-80% it is only an issue if consistently above range
Funny you should say that. During a recent review of my thyroid medication a clinician suggested I might be slightly overmedicated as my T4 was at the top of the range and then there was a comment that middle of the range would be better but he didn't say any more and I was sceptical. Maybe they read the same article! I'd had my blood test before taking my levo so maybe T4 was a bit high. He reduced my dose very slightly and I actually feel quite good, calmer, although it's early days.
How much was the reduction? Glad it’s working out so far.
Hi. He reduced it by 12.5. I was on 75. I was taking a 50 and a 25. He was adamant I should take the 12.5 tablets and not halve a 25. We'll see what happens at the next blood test but OK so far. As thyroxine is a storage hormone I'm aware effects of lowering/raising a dose aren't always felt for a few weeks.
And how early is early days? I have just been through this and I felt ‘brand new’ by day four. Unfortunately only for day four. Another four/five days it happened again. Not so good now though!
Yes, I know this can happen. Also there's other factors in the mix. My vit D and iron levels are much improved now as a very stressful time had caused my physical and mental health to suffer and is only now getting back on track which has helped . Thyroid issues aren't the only problem for a lot of people so it's a very individual thing.
You are not kidding re: individual. Unfortunately that’s the very thing we deal with every day. Hence my querying your particular response.
High FT4 is not a good idea, it's true, but I wouldn't go so far as to use the word 'dangerous'. You're not in any imminent danger, it's just that it increases your risk of cancer and heart problems. jimh111 can explain this better than I.
If you need your FT4 either high in-range or over-range, it probably means that you are a poor converter, but when your FT4 gets that high it starts to convert to more rT3 than T3. And whilst the rT3 isn't a problem in itself, it does mean that the T3 you have is less effective. So, people often find that reducing their levo to bring their FT4 level down, actually improves their conversion. Worth a try. 
Higher fT4 is considered unsafe by me! I've seen increasing evidence that higher fT4 (within the reference interval) are associated wtih increased cancer and cardiac risks. I give details of the cancer risks here ibshypo.com/index.php/thyro... (click on the blue link at the bottom of each page). I hope to update this in the near future.
This post healthunlocked.com/thyroidu... explains a bit about the cardiac risks.
it has struck me that we have the irony that whilst it's generally a good idea to suppress TSH in some cases of thyroid cancer by using levothyroxine monotherapy we are increasing the risk of other cancers. Out of the frying pan into the fire!
This review liebertpub.com/doi/epub/10.... of this recent study e-enm.org/journal/view.php?... now shows that levothyroxine monotherapy is indeed a bad idean.
My view is that levothyroxine monotherapy should NOT be routinely used. Prescribing a little T3 such as 5 mcg twice daily would allow fT4 levels to be in the lower part of the reference interval thus reducing cancer and cardiac risk. My rough guess is that around 1,000 hypothyroid patients die prematurely each year because of levothyroxine monotherapy. It could be fewer or more, the exact number doesn't matter, we don't compute the exact risk when deciding to use a pedestrian crossing.
Thank you jimh111 for the references, asking my Gp to prescribe T3 was a non starter and I’m not in a position to seek private care at the moment. So I will continue my mono therapy journey albeit at a reduced dose.
If you feel OK on a lower dose that's fine. Bear in mind that the risk varies with age, for younger or middling aged people the higher relative risk doesn't add up to much.My aim is to make doctors (and patients) aware of this so that prescribing practice changes.
Thank you, I haven’t coped well on a reduced dose in the past and have kept myself at the top of range in order to cope with a demanding job. I’m older, with less personal life demand these days so will give it a go.
well now you've got me thinkin. Test on 8-1 my free t4 is 1.6 range is 0.8-1.7 then free t3 was 2.4 range 2.0-4.8 TSH was lowest ever at 0.07 range 0.27-4.20. Odd thing is I've been having bouts of sudden high BP 160 /100 with some tachycardia, occasionally, and very weird panic attacks. All this from 100mcg tirosint, steady for 7 weeks. I switched from 88 tirosint with a 5mcg cytomel because of these symptoms. Just wonder if the free t4 along with suppressed TSH could be causing the panic. Just feel like I'm on planet Mars ! And most of the time my heart rate is only 60 . So many theories, and uneducated doc's. Looking into hyperadrenergic pots. It's interesting, and not so uncommon with thyroid issues. Anyway thanks for the good read. Open to all suggestions, and knowledge.
What is considered optimal free t3 levels? 
I feel better with free t4 higher in range.
FT3- is higher always better? 
High T4 and Tachycardia- is there a correlation? 
