I've felt well for a while now so haven't felt the need to read posts every day and I think I might be out of the loop a bit.
I'm just wondering what the current thoughts are on suppressed TSH?
Also (and I could be wrong on this one) but I thought that T4 levels weren't particularly important if you were taking T3 as well?
I promise I will pay more attention in future!
FT3 is the most important number followed by FT4
Both FT4 and FT3 are important
Though medics don't usually understand this and instead focus on TSH often resulting in patients being wrongly dosed
TSH is not a reliable marker....it is a pituitary not a thyroid hormone and is basically a signal to the thyroid gland to produce more, or less, thyroid hormone
..it fluctuates throughout the day. It is highest at 9am.
Taking T3 will naturally suppress both TSH and FT4
Are you feeling unwell? If so post any labs you have and members will advise
No, I'm feeling good! I hadn't really been keeping up to date on things on here, as I felt OK so didn't feel the need, however I recently posted some blood results and as my T3 was slightly over range I was advised to cut back a little on T3, which I have done. However my T4 is only 1.08 (0.89-1.76) and as I mentioned, I was always under the impression that T4 wasn't as crucial once you were taking T3?
Also, I happened to see something on here yesterday from a few years ago re suppressed TSH so did a bit of digging and found it's linked to Afib, which I have. So really, I'm just after a bit of reassurance that a very low TSH is still considered OK (mine is 0.02 - range 0.02-4.78).
I need 100mcg T3-only to function
My TSH has fallen off the scale, it gives me no problems. As I said, it is basically a messenger
You appear to be overmedicated .....this can cause Afib....high T3 will suppress TSH.....so I'd suggest your Afib is caused by your high FT3.... which is reflected in low TSH
Excess thyroid hormone is a well-documented risk factor for the development of atrial fibrillation .
as I mentioned, I was always under the impression that T4 wasn't as crucial once you were taking T3?
That depends on how much thyroid hormone(s) you are taking
Do you depend on T4 to T3 conversion for a substantial amount of the T3 you require? ...If so your FT4 level is important
Like my TSH my FT4 is also on the floor....none of my T3 comes from conversion but from an exogenous source of T3
I wouldn't be concerned about your TSH but I could be concerned about your high FT3
It is all very personal because we are all different.....the numbers that suit A are unlikely to suit B! This is why symptoms are an important factor in diagnosis.
You haven't mentioned how much T4 and T3 you are taking.
If you are feeling "good" with absolutely no symptoms of wrong medication then all is well.....but you have Afib so all is not well. You need to review your dose.
I take it your T3 dose is reasonably high to cause that low FT4.
Thanks for your help. My T3 was 4.22 (2.30 - 4.20) so only a tiny bit over. I have been taking 75mcg T4 and 25mcg T3 but have now dropped T3 down to 18.75.
I've had Afib for about 5 years now, and it started when my T3 wasn't as high so I don't really think that is the cause.
Ah right...Tina has now given you a list of other possibilities
Has your GP mentioned beta blockers?
webmd.com/heart-disease/atr...
Hope you find the answers you need
Take care.
I'm not one for prescribed medication so I asked the consultant if I could lose a bit of weight and do more exercise instead - and to my surprise she agreed! After that I found a Facebook group who rely on alternative methods of treatment so got a lot of help there. Whichever way you go, natural or alternative, there is always a stroke risk but I keep my fingers firmly crossed every day 🤞
My T3 was 4.22 (2.30 - 4.20) so only a tiny bit over
Maybe bear in mind that although your labs are in range the number(s) might still be too high for you. The ref range is just a guide.
We aim for roughly 75% through the ref range
Your FT3 result is 101.05% through ref range.
Too high for most people
thyroid.dopiaza.org/?utm_so...
Monitor how symptoms go on 18.75mcg...
25mcg to 18.5mcg ia a big drop (7.25mcg) in a single step. Might be a bit of a shock to the system....but we all respond differently!
I'm sure you will check that any advice you follow on FB is from a reliable source!
Good luck!
I must admit I didn't feel "over" at all but maybe things might have developed if I'd stayed on that dose much longer.
I must be being a bit dim but I can't see how I could have done anything else than reduce to 18.75 as it already involves splitting quite small tablets into quarters. I've only been on 18.75 for less than two weeks so do you think it would be too late to add an eighth of a tablet (though it'll probably end up as dust!)
How long were you taking 25mcg T3?
I take it your GP knows this.
If you've now been on 18.75mcg for about a couple of weeks and feel ok I'd stay on that dose for a total of 6 or 8 weeks to let the dose settle then test again.....at least TSH, FT4 and FT3.
I wouldn't alter my thyroid meds just to raise my TSH.
Absolutely not, that is putting the cart before the horse!!
You alter your thyroid meds to achieve a result that gets rid of symptoms...TSH is a reflection of that effect not a guide to dosing!
Symptoms are an important part of diagnosis....not just numbers!
FT4 and FT3 are the guides.....aim for roughly 75% through th ref range ....easy calculator in my earlier reply.
Who diagnosed Afib? Are you being monitored?
Hope things improve soon.
Just to explain a bit, I live in Spain and have private health insurance but my Hashimoto's is a pre-existing condition so not covered. My doctor is a nice lady but when my blood results come back she just pronounces everything as normal (even when it's not!) so I pretty much have to look after myself. I've been taking 25mcg for a few years now and have felt fine.
My Afib was diagnosed by a cardiac consultant at hospital here. As I mentioned, I opted not to take medication so I look after myself on that score too, but luckily because I've identified my triggers, I don't suffer from attacks too often.
Goodness, it's hard isn't it.
I've had to take over my thyroid treatment, endo, couldn't diagnose me and wouldn't offer T3. So I hit the internet and researched for months until I discovered that I have a form of Thyroid Hormone Resistance and need a huge dose of T3-only, initially that would knock a cart horse out!!
I was taking 200mcg T3 for a while with no problems until I started to feel overmedicted. It seems some of the dormant thyroid hormone receptors had been reactivated by the blast of T3....so I needed less hormone to achieve action!
Not a technical explantion but just mentioning this in case it might ring some bells!!
Stay as well as you can be.
Wow that's interesting! Well done for being a Grade A researcher 😊
The TSH is actually not a thyroid hormone. It is a signal from your pituitary gland in response to thyroid hormones. So when hormone levels are high, the TSH goes low and thyroid production slows down or stops and when thyroid hormone levels are low, the TSH rises, so the thyroid kicks into action and produces more hormones. This is in a NORMAL thyroid and this feedback works very well.
However, in thyroid disease this feedback can be unreliable and especially when you are taking thyroid hormones it can mean that your TSH gets low (or even suppressed) even though your actual thyroid hormone levels are still low or not optimal. As many GPs (and also endocrinologists sadly) dose by TSH, this will leave some thyroid patients on too low hormone levels, as the TSH is not a reliable mirror and can no longer guide treatment. This is why it is important to look at the free T4 and T3 levels and these should really guide treatment decisions, as the TSH cannot be relied on. I am attaching a paper that describes that the TSH-T4 axis is frequently broken and that free T4 and T3 should be used for guidance. The paper mentions levothyroxine treatment, but it can be applied to other treatments as well.
pubmed.ncbi.nlm.nih.gov/293...
There are several risk factors for atrial fibrillation:
Age: The risk of AFib increases with age.
High blood pressure: Long-term high blood pressure is a major risk factor.
Obesity: Being overweight or obese increases the risk of AFib.
Heart disease: Underlying heart disease, such as valve problems, cardiomyopathy, or a history of heart attack, increases the risk of AFib.
Diabetes: Diabetes is a risk factor for AFib.
Alcohol: Binge drinking and heavy alcohol use are risk factors for AFib.
Smoking: Smoking is a risk factor for AFib.
Sleep apnea: Obstructive sleep apnea is strongly linked to AFib.
Family history: Having a family member with AFib increases the risk of developing it.
Stress: Feeling stressed or angry can increase the risk of AFib.
Hyperthyroidism is also associated with atrial fibrillation, however hyperthyroidism includes increased (over range) levels of T4 and T3, which lead to a suppressed TSH. If you have a suppressed TSH but your thyroid hormone levels are within the range, this is what they call subclinical hyperthyroidism (which I think is a misclassification).
If you take T3 (or even some people on T4 only), your TSH can get quite low or even suppressed, but that is a normal response to treatment and as long as your free T4 and T3 are in range, this should in general not cause any problems. However, it also depends of course on your own personal patient history and any other conditions you may have. A low or suppressed TSH alone will not give you osteoporosis or AF, it very much depends on the other risk factors, if you develop the conditions.
With every medication we take there needs to be a risk-benefit assessment; if you need T3 or more thyroid hormones to feel well and your TSH gets low or suppressed, then that is a risk you need to weigh up for yourself and decide, if perhaps a slight increased risk of a condition might worth the quality of life you have by ignoring the suppressed TSH and closely monitoring your thyroid hormones and symptoms.
Thanks for your help. My T4 is low but still in range and my T3 only a tiny bit over. I've reduced my T3 to 18.75 so hopefully that will help. As far as the Afib goes, I reckon I have got it now and I wouldn't alter my thyroid meds just to raise my TSH.
I am very lucky that I don't get Afib attacks very often. I've probably only had about 6 in all the time I've had it. I don't take meds (Thyroid meds are quite enough to contend with!) but control it as much as I can with supplements. I have cut right down on alcohol, only drink decaf coffee and am very careful re anything else that might act as a stimulant.
Glad that you are on top of your thyroid medication, hopefully you are finding your sweet spot soon! 
It is good the AFib is not too bad, but just to reassure you, there are some modern medications that are actually quite good at reducing the symptoms, should it ever become bothersome.
Take care!
Hi, I'm interested in reading the link, but alas it's not working for me. Is there another way to read the article?
If you click on the link then you should get a redirect notice, then just click on the blue link and you should be OK.
YES - EuropePMC:
I click the link but a notice came implying I could not gave access. I even tried pulling out of Thyroid uk and trying again.
Hi there, I just tried to follow the link but I could not, I think the pub med server might be down at present. Maybe try it in a couple of hours again and see?
Yes, Pub Med servers are currently down. See this post healthunlocked.com/thyroidu...
Suppressed TSH
'Suppressed' TSH
Query about suppressed TSH
Suppressed TSH
Suppressed TSH
