I am looking for some advice having recently been put on block and replace treatment for Graves' disease by my endocrinologist.
A bit of background info:
I was diagnosed with Graves' disease nearly two years ago in August 2021. I have taken carbimazole since, starting first on 30mg and for the past several months on 20mg. However my levels are still very labile and I still have high TRAb and low TSH. My most recent blood results (23/5/2023) are as follows:
TSH: 0.06 (0.27-4.2)
Free thyroxine: 12.7 (12.0-22.0)
Free T3: 4.5 (3.1-6.8)
TRAb: 6.5 (1.51-3.00)
I am starting block and replace therapy on 40mg carbimazole and 75mcg levothyroxine per day. Would be good to hear any advice/experiences from those who have done block and replace as well as those who just take levothyroxine. For example, I'm not sure if I should take in the morning or at night? With food/without? At the same time as the carbimazole or different time? I also take vitamin D and selenium supplements - is it best to take all together or to spread out? What signs should I be looking out for that the levothyroxine dose is too low/high?
Thank you very much in advance!
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Liv8523
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Hi liv, I have been on B and R about 6 years. It has kept me feeling well although I need the occasional adjustment.
I started on 20mg Carb./ 50mcg Levo. However, I wanted to be on the lowest effective dose and after a bit of experimenting this was found to be 10mg C/50mcg.L. To feel well my fT3 needs to be half way through range so I adjust to keep it at that level. I can tell by using my resting pulse if I am going hyper or hypo. Normally it is in the 60’s going down to 50’s if hypo and climbing up if hyper. Over the years I have been tending towards hypo and currently take 5mg C/100mcg L.
You say you have high TRAb and low TSH. I wouldn’t consider 6.5 VERY high. I went on BandR because TRAb was high at 16. I presume your TSH was suppressed initially so if it is now 0.06 it is creeping up which is a good sign and it may be enough to start titrating Carb down from 20mg. because at the moment you appear to be hypo. Personally I would be tempted to try titration first but I don’t know your past history and you say your results have been labile.
It works for me to take the Carb and Levo at the same time in the morning on empty stomach.
Thank you very much for the info and advice. It is interesting that you can tell if you're going hyper/hypo by testing pulse - I will start paying more attention to my pulse! Great that you've felt well on B and R for so long and on a low dose.
I'm not sure why my endo has started me on such a high dose for B and R. I have tried titration for the past nearly two years but every time my carbimazole dose has gone below 20mg I have become hyper again. I think this was because I still had such high levels of TRAb (28 when first measured then dropped very slowly to 12 this January and finally around 6/7 since March.) And yes my TSH has been <0.01 at all previous blood tests so good that it is starting to creep up.
Going to see how I get along with B and R over the next couple of weeks. Thanks again for the advice and support!
Graves is an auto immune disease for which there is no cure and something has triggered your immune system to turn and attack your body, rather than defend it.
Graves is usually diagnosed when the eyes and or thyroid are involved and Block and Replace a treatment option offered while we wait for your immune system response to calm down.
Graves carries both stimulating and blocking antibodies and during this first phase of the disease you can experience a roller coaster of symptoms and also times of relative wellness when these two extremes burn each other out.
You may well feel totally exhausted just sitting on the sofa and feel you need to run another marathon, eating for England though losing weight, nervous, anxious and just uncomfortable within your skin.
When taking just an anti thyroid drug, such as Carbimazole or PTU, the endocrinologist tries to adjust and part block your own thyroid function to regular blood test readings so to try and ' keep up with the action' and relieve any further symptoms you maybe experiencing.
However blood tests are just a snapshot in time, and do not explain the full effects of this AI disease and tend to run behind symptoms being experienced, by a few weeks.
Since there is no way of controlling either the blocking or stimulating antibodies at any one time some endo's suggest the Block and Replace treatment option.
In this way the dose of the AT drug is increased to fully block your thyroid function and a measured dose of T4 - Levothyroxine - the main thyroid hormone your thyroid produces - is prescribed so your T3 and T4 levels do not fall too far through the ranges causing you to experience the equally disabling symptoms of hypothyroidism.
Both treatment options offer the same goal which is to ' buy time ' while we wait for your immune system to calm down and for your thyroid to revert to normal and your Graves to have gone into remission or burnt itself out naturally and or your bloods showing negative Graves antibodies.
Graves is poorly understood and the badly treated - but the most recent research we have is suggesting the longer the patient stays o the AT drug the better the long term outcome for the patient :
I have Graves and went through RAI thyroid ablation is 2005 and deeply regret this treatment, though not given any option at the time and knew nothing -
You might like to read around Graves and the most all encompassing website is that of Elaine Moore who also has Graves and having gone through RAI found her health and well being further compromised.
Check out Elaine's sections on alternative, more holistic treatment options and look at what you can do for yourself to calm down your immune system response which might be reassessing your life / work balance and your own ' triggers ' as common factors appear to be stress and anxiety related , though there could also be a genetic predisposition with someone in your extended family, maybe a generation away from you with a thyroid health issue.
When metabolism is running too fast as in hyperthyroidism or too slow as in hypothyroidism the body struggles to extract key nutrients through food - irrespective of how well, fresh and clean you eat and your core strength vitamins and minerals are liable to fall through the ranges compounding your health issue further.
It would be a good idea to get current readings of ferritin, folate, B12 and vitamin D as these all need to be maintain at optimal levels for any thyroid hormone replacement to work well - and that includes T4 - Levothyroxine.
You might like to also dip into Thyroid UK - the charity who support this forum - where you can find much more detail about all things thyroid - thyroiduk.org -
Since you are starting a new treatment regime another good idea is to keep details of the symptoms being experienced and hopefully relieved by the medication, and also add in any new symptoms that appear so you have some insight and input at appointment to help guide the endo's opinion as to a way forward rather than just be a mathematical equation on the computer.
You can then offer experience rather than the endo just rely on blood tests to try to assess if your dose of either the Blocking drug - Carbimazole or the Replacement dose of T4 - thyroid hormone needing adjustment and in reality start to become your own best advocate at ' reading your body ' - which we all seem to end up doing anyway - as a blood test is limited and one dimensional, and we are much more complex than a computer print out.
Hello there, When I was on block and replace I used to take my carbimazole at night before bed and then take my levothyroxine when I got up in the night to use the toilet.I alway made sure to leave at least 4 hours between.I could then eat breakfast as soon as I got up as it would be more than 1 hour since I took my levo.Hope this helps.
Thank you for replying and the advice! Is it best not to eat until at least an hour after taking levothyroxine then? Do you know why this is? My plan was to take as soon as I wake up and then have breakfast around 30 minutes later - is this not long enough?
Hello again, I believe it is best to wait an hour after taking levothyroxine before eating.This is what is recommended on here.Food and particularly caffine can affect absorbsion of it.That is why I take it when I get up to use the toilet during the night.My stomach is virtually empty and I can eat as soon as I get up.Also I take other tablets and supplements , so I take those before bed and it is normally at least 4 hours before I take my levo.Some other medications and / or supplements can interfere with the way levo works and vice versa so that way I leave plenty of time between them.I was on block and replace for nearly 3 years and on the whole it worked OK for me.I did however have a total thyroidectomy last June and I am doing well on levo only.My reasons for not continuing on block and replace were that I had a bad relapse when I tried to come off it to see if I was in remission from my graves , and that my T4 levels still fluctuated while I was on it resulting in frequent and bad migraines which got me down.I also have TED(thyroid eye disease).
I asked for the thyroidectomy myself as I had had enough and believed I had given everything a good go.You can read my story if you click on the picture at the side of my name.I have kept it up to date.Please don't think this would be your experience, we are all different and different things work for different people.As long as you have regular blood tests every 6/8 weeks to track your progress it is a good regime.Wishing you the best of luck.
When I was diagnosed in 2012 I was put on B&R to see if my thyroid it would settle but it never did. So I had the medium dose of RI and since then (touch wood) I have been fine on 100/125 levo on alternating days.
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