Hello all. I am a thyroid cancer survivor after a total thyroidectomy. I have never posted anything on this forum just mostly stalked ;).
I have been feeling terrible for awhile and in November I found out that my fT3 was very low which would explain it. It has been a very long road at trying to get adequate replacement. Med adjusting and lab draws.
Well I am getting ready to have labs done again because I am still feeling the same and have seen that people here recommend fasting for thyroid labs which I have never been told to do. Can someone please explain? Thank you in advance for the clarification.
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Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and fasting. Last Levothyroxine dose should be 24 hours prior to test, (taking delayed dose immediately after blood draw). This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)
For full Thyroid evaluation you need TSH, FT4 and FT3 tested. Also extremely important to test vitamin D, folate, ferritin and B12
Low vitamin levels are extremely common
Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or all vitamins
Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random
After full thyroidectomy it's likely you may need the addition of small dose of T3
New NHS England Liothyronine guidelines November 2018 clearly state on pages 8 & 12 that TSH should be between 0.4-1.5 when treated with just Levothyroxine
Note that it says test should be in morning BEFORE taking Levothyroxine
Fasting is recommended when the TSH result is important - mainly for people who are looking for a diagnosis or want to avoid a reduction in their dose of Levo, or are looking for an increase in dose. In these cases then the highest possible TSH is needed, which is achievable by having the earliest possible blood draw - no later than 9am - and fasting from evening meal/supper the night before because eating might lower TSH - see post by Diogenes (scientist and advisor to TUK) here where he says in 9th reply down in response to a question by Humanbean
"TSH falls after eating, but FT4 not affected. Don't know about FT3 but suspect it will behave like FT4."
Some patients believe fasting makes a difference to the TSH result, I do not as I've never seen any good evidence that it does. It's important not to take your thyroid hormone tablets within a few hours of having the blood taken.
The recommendation to have the blood taken early morning is to get a TSH figure that is a little higher, which may not help if your problem is that your TSH is too low (not reflecting your hormone levels). A low TSH can lead to impaired T4 to T3 conversion. Thyroid cancer sometimes leads to a period of thyrotoxicity (high thyroid hormone levels), this can suppress TSH production by the pituitary and sometimes the pituitary does not recover leading to abnormally low TSH levels.
It's important that they measure your fT3 as well as fT4 and TSH. Remember to ask for a copy of your results and post them here.
Yes, I also " stalked " for a time before jumping in.
Just as a point of reference, a fully functioning thyroid gland would be supporting you daily, with approximately, 100 T4 and 10 T3.
Some people do well on T4 alone, some people simply stop converting T4 to T3 and some people need both these hormones supplemented and monitored independently to achieve a level of wellness for the patient.
it's also important that all vitamins and minerals, as detailed on this amazing site, are optimal as they will then optimise the utilisation of the thyroid hormone replacement.
I don't know what medication you are taking, but if your prescription doesn't include both these essential hormones maybe this is an area you might like to discuss at your next appointment.
Thank you pennyannie. I have been on T4 only replacement since 2010 and probably haven’t felt optimal since then, although it wasn’t until the last couple of years that I have felt worse so I insisted on my endo testing free T3 because up until then she had only monitored fT4 and TSH. In November it was very low and so she put me on 5 mcg/ day of T3 replacement. I felt no difference and that was all she was willing to put me on. So I went to someone else who checked it and it had dropped even more.
He put me on a delayed release T4/t3 compounded medication and told me to have labs done in one month if I wasn’t feeling better and two if I was feeling better. We are at the month because I don’t feel better so that was where my question stems from.
So impatient At how long it takes to get yourself to optimal place with meds. I do have hope with the new guy though thyroid I will eventually get there and get my life back.
I just have to be patient. Thanks again for your response!
Please let us know what is this T4/T3 compounded medication - how much T3 to T4 per tablet and how many tablets are you taking in any 24 hours.
Yes, 5 mcg T3 wouldn't have been enough to make much difference. It's not that it didn't work, but you weren't given enough, in the first instance.
Yes , it does all take some time, but then you've been struggling for a while, so it's a slow build back up to wellness.
It will be prudent to get your vitamins and minerals checked out as these need to be optimal for any thyroid hormone replacement to work effectively.
You might like this book :- Your Thyroid and how to keep it Healthy by Dr Barry Durrant Peatfield. This English doctor has hypothyroidism, it's such a good, easy to understand, common sense read.
We may not now have thyroids so we need to work extra hard to compensate for the lack. It is a major gland responsible for your body metabolism and your physical, mental, emotional, psychological and spiritual well being.
Some people refer to it as the conductor of your body's orchestra.
I'm with Graves Disease post RAI thyroid ablation in 2005 - I was only ever on Levothyroxine, became very unwell about 4 years ago.
I'm now self medicating with Natural Desiccated Thyroid, doing ok and getting my life back.
The medication is made at a compounding pharmacy that mixes the levothroxine and liothronine with an agent that makes it slow release (12 hours). It does make it less absorbable because of the compounding agent so they increase the medication by 25%. So my dose right now is 135 mcg T4 and 15 of T3. My original T4 when I was on T4 only was 125mcg.
So happy for you that you have your life back. I can’t wait to get mine back!!
It's a slow build but I am much improved with NDT -
This is pigs thyroid - and was the thyroid treatment for over 50 years, prior to the introduction of Levothyroxine and blood tests in the 1960s.
You dose to alleviate symptoms, as if you take too much, you soon know about it, and simply drop back down to where you were before.
Blood tests as we know and love/hate them, being irrelevant.
Some" old school " and specialist doctors do still prescribe this but as BigPharma aren't able to patent and commercialise on this product, it has been discouraged by the medical industry.
It has a ratio of 4/1: T4 to T3 and one tablet contains 38 T4 / 9 T3.
As you feel no better it might simply be that ratio of the T3 to T4 needs to be increased, and am sure that isn't a problem, as we all need " fine tuning and adjusting " as our lives evolve.
I hope you find some improvements, stop stalking, and loiter with the intent of sharing your experiences so we all can learn from each other and widen our knowledge.
Interesting, thank you for that input. I think it is just not an adequate t3 dose but will keep that in mind. I was on 5 mcg of T3 that was not delayed release and felt no change if not worse. You say that they will not work? So that should be reflected in my labs?
Most common dose seems to be 15mcg or 20mcg. Often as divided dose
Personally I find 3 doses per day, 8 hours apart works best. (10mcg at 7am, 5mcg at 3pm and 11pm. Plus Levo at 11pm)
On almost any dose of T3, TSH becomes suppressed. Essential to always test FT3 and FT4. Plus vitamin D, folate, ferritin and B12 need to be optimal
Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and fasting. Last Levothyroxine dose should be 24 hours prior to test, (taking delayed dose immediately after blood draw). This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)
If/when also on T3, make sure to take last dose 8-12 hours prior to test
Obviously this time recommendation probably won't apply to slow release T3. That probably needs to be 24 hours delay
Just in case it isn't clear, fasting only has to be done overnight and before the blood draw. So, if your blood is being taken at 8.30am on a Wednesday, then you would fast (apart from water) from roughly 10pm - midnight on Tuesday evening until after the blood draw on Wednesday morning.
Hi to all who have replied to this post - can you tell me when I should have my last dose of Levo before having my blood test by approximately 8.30 am as I have decided to take my levo before bed and not in the morning as it suits my routine better?
Last dose of Levo before the blood draw should be 24 hours before.
If you take any T3 or NDT then take the last dose of either 12 hours before the blood draw, although I'd like greygoose or SeasideSusie to confirm that. Some people leave a smaller gap.
The important thing to remember is that, whatever delay/gap you use, that you note it down and always use that delay in future, so that you can compare tests to each other with more reliability.
Many thanks Humanbean - I'm only on Levo. I think I found another reply as I was scrolling that it is more important not to eat or drink before my blood test when it's just a TSH test.
Time of day is hugely important for a TSH test - it has a circadian rhythm that alters the level of TSH throughout the day. You want to produce a result that is as high as possible to a) get a diagnosis (if necessary) , b) get an increase in levo if you need one, c) avoid a reduction in dose.
See this thread and pay particular attention to the graphs.
As far as blood tests go, the result of a TSH test is affected by the time of day that the blood is taken. TSH changes quite slowly as a result of dosage changes. So delaying a dose of Levo or T3 or NDT in the 24 hours before a blood test, or changing the time it is taken will have no noticeable effect on TSH.
However, changing the time that thyroid meds are taken in the 24 hours before a blood draw will affect Free T4 and Free T3 levels.
If you tell us what thyroid meds you take and when your blood will be taken (day and time), then we can suggest when you take your meds to give worthwhile results.
Some people stop taking their thyroid meds for days before testing, which is utterly pointless in my view. You won't learn anything from the results!
Many thanks for your help. I have just re-started Levothyroxine after a seven week break (Doctors orders , duh) and I thought I would try taking it at bedtime instead of in the morning as I couldn't cope without my morning cuppa, having to wait an hour was not good for me. I'm not due to have a blood test for six weeks but wanted to arm myself with as many options as possible before the event. I think I've seen another post regarding timing of dose which I think would suit me, in effect, not taking levo at night but moving the dose to the following morning the day before having the blood test. Have it as early as possible, with fasting, take my levo immediately after the blood draw and then going back to normal that evening. I have just started taking a VitB complex which I must stop taking a week before my blood test as it contains biotin. There are a lot of things to remember.
Suppose you book an appointment for the blood draw on a Wednesday morning at 8.30am.
On Monday take your Levo at bedtime as usual.
On Tuesday take your Levo at 8.30am.
Eat and drink normally until roughly 10pm - midnight then fast, apart from water which can be drunk freely, until after the blood draw. Don't be dehydrated.
On Wednesday, once the blood has been taken, eat and drink as normal. Take your Levo at bedtime as usual.
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