I have Graves’ disease but my thyroid is very erratic and it changes from one extreme to the other and is making me quite ill. I was on propylithouricil for months to get it under control as I was intolerant to Carbamozole ( I had it a few years back but can’t remember why I switched to propylithouricil ) but the Endocrinologist really wasn’t happy with me being on the former drug as it’s not good for the body and so I’m trying Carbamozole 40mg again it’s okay so far. The thing is as it’s so unstable my Endocrinologist has suggested we try a block and replace. I only know what I have read but it’s vague how it actually is instigated and the effects and experiences. Can someone enlighten me, maybe on it and know what I should expect if this goes ahead. Many thanks
Block and replace method. : I have Graves... - Thyroid UK
Block and replace method.
Hi Suffolklady, I can explain my own journey on Block and Replace in the hope it helps. It comes with the caveat that everyone’s journey with Graves can be different. Docs often use B&R to keep us more stable and reduce the blood tests needed. They often use a high dose of Carbimazole 20 - 40 mg. to block our thyroid hormone production and add in about 100 mcg. Levothyroxine to replace what we have stopped producing. Because I responded well to Carbimazole and suspected I would be on it long term due to my high TRAb antibodies, I wanted to be on the lowest effective dose to keep my fT3 about half way through range where I always felt well. After a year of trial and error I settled on 10 mg.C/50mcg. L which needed slight adjustments over the next few years as I became more Hypo Graves. Currently on 5mg.C/ 75mcg.L. After 8 years ( you can read my bio.) I am slowly weaning off meds. to check for remission which I think most of us will eventually achieve. It has been useful to keep a note of dosage / blood results/ symptoms to chart my journey.
I will read your journey after I’ve replied. I'm on 40mg Carbimozole atm. It’s because it was going higher. I haven’t always been on medication it was fine for 18 months then went over active. I already have lots of meds back issues high grade pain killers, adrenal insufficiency so I’m on steroids. I don’t want to feel any worse than I do now by accelerating my thyroid output then taking levo if it’s going to be hard to get it right. I know I have no chose he mentioned ablation (not sure if I’ve got the right word but that sounds to drastic.
Having adrenal insufficiency and taking steroids will probably affect your thyroid and I wouldn't feel I know enough about this to comment. I expect the 40 mg. Of Carbimazole you are taking at the moment will likely put you back into the cycle of fluctuations and that B&R is worth a try. You have complicated issues going on and I wish you all the best and glad you have confidence in your endo.
Carbimazole is usually 1st choice, PTU is then used if carbimazole not well tolerated.
Carbimazole can be taken in fewer pills, whereas PTU often has to be taken in many to have same equivalent effect.
Block and replace involves a higher dose of anti thyroid to block all natural thyroid function. As you won’t have natural supply you need to take a replacement hormone to restore levels. Levothyoxine (L-T4)
There are a few members who managed well on “B & R”. It will help stabilise those unexpected fluctuations. It is also used if FT4 & FT3 are unbalanced. Eg FT4 fall low but FT3 is still high.
Down side of Block & replace is that you need a higher dose or anti thyroid. it will also hide what your levels are naturally doing. So if levels are naturally resolving there would be no sign to indicate it. Stopping block & replace is more difficult to manage too. Do you stop both at once? tweak either carbimazole & / or Levo ? Doctors do not always manage this aspect well.
It might be you have Graves which is difficult to manage causing fluctuations or is is possible your not being managed appropriately?
How often are you monitored? Are appropriate adjustment being introduced on time?
Do you have access to your blood test results? Many of us have set up online access to view then or you can obtain printed copies. You need a copy as it must include lab ranges. (Ranges vary between labs, do need for each test. Even if tested in same location / arrange by same doctor. Ranges can change)
Obtain your results & we can explain them to you. For full thyroid function you need the following.
TSH, FT4, FT3
TPO & TG Antibodies TSI & IR TRab to confirm Graves
Also important to test
Folate
Ferritin
B12
Vitamin D
Gluten issue common with Graves has this been tested?
I completely agree Docs. don’t manage B& R well and use higher doses of ATM that mask natural levels which make stopping more challenging. However it doesn’t have to be this way. I believe the above problems can be overcome by persistence in finding the lowest effective dose. Many Graves patients on long term B&R will achieve remission. Many become hypo - either temporarily or permanent. This trend can be picked up on low dose B&R by measuring fT3. If it is reducing, a little more Levo can be added. Stopping B&R is no more complicated than stopping Carb. alone. You reduce slowly monitoring symptoms and fT3. You can adjust Levo if necessary. The problem with B&R is finding a doctor prepared to go on this journey with you and carry out the necessary blood tests and adjustments needed to keep you feeling well.
7th July. 23
TSH. 4.64. (0.27-4.20)
T4. 19.2. (12.0-22.0)
T3. 5.1. (3.1- 6.8)
TPO. 34 NEGATIVE
34 BORDERLINE
34. POSITIVE
TPO NEGATIVE. (ANTIBODIES NORMAL NO ACTION)
August 2nd 23
T4. 19.2. (12 -22)
T3. 5.1. (3.1- 6.8)
Oct 23
T4 is 31 i think
REVIEW IN 12 WEEKS TIME.
12th December 23
T4. 37 (12-22)
T3. 8.5 (3.1 - 6.8)
TSH 0.05 (0.27 - 4.20)
PTU 50mg x2 a day
17th January call from 111 in evening.
T4. 44 (12-22)
PTU UPPED TO 200MG
There is just a few things to look at. As you can see I’m stable for awhile and then all of a sudden it changes. I can feel it in myself when I am going into hyper. I have my endocrinologist do my bloods at the surgery and it goes through to Ipswich hospital. He always rings the next day without fail. My bloods are taken every six weeks and have been for quite some time at least 18 months. I must say the care I get from my endocrinologist is excellent but it doesn’t alter the fact I feel so rough all the time. Years ago I was under active and on levo. Then it went through the roof 100 T4 but with immediate medication it came down. All the other obs are fine.
No I don’t access my notes unfortunately. I really don’t know how it works. I would be interested though. I think it would be an idea. I get print outs for the GP bloods but the thyroid one is on a different system as it goes to the Endo department so I write it down when I get the call from consultant and it’s sometimes in the GP letter he gets from Ipswich hospital.