Just wondering if anyone knows how you can tell if you are not absorbing thyroxine and liothyronine due to gut/stomach problems. Will your TSH and T4/T3 blood levels show you have enough hormone - i.e. will it still get into your blood but not other parts of your system. I currently have a diverticulosis stricture which is being looked at and had my thyroid medication - T3 reduced back in Feb from 15 to 10 due to my low TSH. I still have many, many symptoms of hypothyroidism such as low body temperature, fatigue , constipation, brain fog etc. My latest results at the end of July through Medichecks were:- TSH 0.064 (0.27-4.2), T4 14.1 (12-22), T3 4.3 (3.1-6.8) . I also have B12 deficiency and have 3 monthly injections , I'm also often have low in vit D and folate and so take supplements.
Problem absorbing T4/T3: Just wondering if anyone... - Thyroid UK
Problem absorbing T4/T3
It will not get into your blood.
You would expect lower FT4 and FT3 than if there were no gut issues - and higher TSH. And the consequences of being under-dosed. Though absorption of T4 and T3 might be differently affected. That is, you could find absorption of one is at 50% and the other at 75% (or any other numbers!)
There is a reasonably strong possibility that every three months is insufficient for B12 injections.
I very strongly suggest you also post on the Pernicious Anaemia Society forum:
Thank you for your reply and link. I think you're right about the 3 monthly injections, I will bring this up with the GP again.
Free T4 (fT4) 14.1 pmol/L (12 - 22) 21.0%
Free T3 (fT3) 4.3 pmol/L (3.1 - 6.8) 32.4%
Recommended that all thyroid blood tests early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)
T3 ….day before test split T3 as 2 or 3 smaller doses spread through the day, with last dose approximately 8-12 hours before test
is this how you did your test
Assuming yes…
your results show you aren’t on high enough dose levothyroxine and probably also need more T3 as well
Ignore TSH
how much levothyroxine are you taking
Get 12.5mcg increase daily initially
Retest in 6-8 weeks
Meanwhile work on maintaining GOOD vitamin levels
B12 deficiency and have 3 monthly injections , I'm also often have low in vit D and folate and so take supplements.
Please add most recent results and say exactly what vitamin supplements you are taking
You may need more frequent B12 injections
Do you have PA or just low B12
Are you vegetarian or vegan
Many people find when adequately treated they will have Ft4 and Ft3 at least 60-70% through range
Thank you for all your help. I always do my blood tests as you suggest, I'm taking 75 levo and 10 lio currently. I don't know whether I am just deficient in B12 or have PA, the GP said its "probably" PA. I eat meat and fish so no reason why I should be deficient. I haven't had my vitamins checked for a few months but vit D has been under 50 previously and folate very low. I now take Thorne B vitamins and Better You Vit D with K as recommended here. You have confirmed my feeling that I'm undermedicated for hypo and B12 too.
75mcg is low dose levothyroxine
How much levothyroxine were you taking BEFORE starting T3. What was Ft4 on just levothyroxine
Frequently levothyroxine dose is lowered too much or doesn’t need reducing at all as Ft4 tends to drop as T3 is added
Low vitamin levels are direct result of being hypo as this results in low stomach acid and poor nutrient absorption as result
Thanks Slow Dragon, I was put on 50 levo and then 15 lio added as the consultant felt I didn't convert well in 2018. I think my free T4 was 12.9 then and free T3 3.98 I was increased to 75 levo later as I was still experiencing symptoms. I stayed on this dose until Feb this year when it was reduced due to concern over low TSH and the consultant thought I may have CFS and not hypothyroidism. My free T4 has ranged between 10.1 and 15.8 and T3 3.7-6.1 over the time I've been medicated.
I think my free T4 was 12.9 then and free T3 3.98
My free T4 has ranged between 10.1 and 15.8 and T3 3.7-6.1 over the time I've been medicated.
What’s range on Ft4 and Ft3
Ft4 looks extremely low
Looking like T3 was added far too soon
Typically Levo dose is increased slowly upwards in 25mcg steps until Ft4 is at least 70% through range ( typically that’s approximately 1.6mcg per kilo of your weight per day)
And essential to maintain OPTIMAL vitamin levels
If Ft3 percentage through range remains significantly below Ft4 percentage through range……only then is T3 considered
This is because adding T3 will always significantly reduce or suppress TSH making it far harder to get dose levothyroxine/T3 increases
Most people on levothyroxine plus T3 find they need BOTH Ft4 and Ft3 at least 60-70% through range
Essential to test with correct timings too
tests early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)
T3 ….day before test split T3 as 2 or 3 smaller doses spread through the day, with last dose approximately 8-12 hours before test
There are two different kinds of absorption problems. One is in the gut, where it doesn't get into the blood. And that would show up as helvella states. Although that would be difficult for you to recognise right now due to the recent reduction in dose of T3. You have a bad doctor, there. He should know that when taking T3 the TSH is going to be low, and in no way does that mean that you are over-medicated! That's just what T3 does and it doesn't matter.
Second is absorption at the cellular level - i.e. thyroid hormone not getting into the cells. As there are no tests to see what is happening inside the cells it's a bit of a guessing game. But the indication is that you have good/high levels in the blood, but still a lot of symptoms of hypo. This is not your case because you don't have high levels of thyroid hormone in the blood. You are just under-medicated and your doctor should not have reduced your T3.
As you are having B12 shots, are you also taking a daily B complex? The Bs all work together and need to be kept balanced. 
Thank you greygoose that's helpful and confirms what I was thinking. I am taking a B complex as I've seen in blood tests that folate levels are sometimes low.
Good.
saving your post as you are in similar situation to me, I’m on t4/t3 and have PA low vit d and folate, have to supplement all the time. It’s very frustrating isn’t it. I’m afraid I have no quick solutions other than what’s already been said but will follow any updates with interest.
Hi Mag99, thanks for your reply. Interesting you have such similar results as I do, as you say very frustrating. Will let you know if I find any answers.
Hi Rosemary,
I have all of the issues that you have listed. For me, it was crazy high amounts of hormones with very high TSH with below normal or barely at normal t4 and t3.
Examples - At some point on NDT I was taking three plus grains and my TSH was in the twenties and as high as 32.
When I added t3 with t4, my t3 level was still low and even dropped at one point with a high TSH as well.
Right now I am on an extremely high amount of levothyroxine (275 mcg possibly heading to 300 mcg) with a 'good' TSH, and T4 & T3 around 50%. And I feel relatively well.
Hope that helps.
Like others are saying you are probably just undermedicated.
(I self-inject b12, even telling my GP, and often inject about every two weeks. When I was diagnosed five years ago I went every other day until no improvement in symptoms per your own UK protocols when there are neurological symptoms - still getting my monthly cyanocobalamin shot from doctor's office- that took about a year to have no improvements)
All the best to you.
Hi Litatamon, thanks for your reply. It does seem very common for people who have a thyroid problem to also have B12 deficiency. Glad you are feeling relatively well.
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