Trying to understand the NDT dosing and if it's working for me.
They say 1 grain of Erfa is about 100 McG of levo.
However, 1 grain only gives you 38 McG of T4.
So if I was on 88 McG of levo before NDT and I now take 1 grain of NDT instead, I only get 38 McG of T4?
How does the 1 grain equals approx 100 McG of T4 add up?
I upped my NDT from 0.5 grain initially to 1 grain and been on 1 grain for a week. But since that increase, I have gotten more tired for some reason vs feeling better from more meds, with head pressure and brain fog and feeling very tired and having more anxiety. Also, falling sleep issues and I usually sleep great. I felt better on less NDT, calmer, more centred and clearer in my head, and good energy. Yes a bit slower and under-medicated, but better than now. Perhaps because I had more T4 in me back then as I just made a switch from levo to NDT?
My BP and pulse is fine, I measure it several times a day.
I tried taking 1 1/4 grains today, made no difference to tiredness and even more head pressure, brain fog, and anxiety.
How can I tell if NDT is working and I should keep at it to give it more time, or if it's not working and I should go back to levo, or levo and NDT combo perhaps?
I have work and kids and can't be chilling in bed all day long with these symptoms!
Thank you for your help!
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Juliet_22
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Thank you so much, that was an interesting read! So it is very personal and doesn't seem to correspond that well. Hmmm, wish thyroid was an easier area to solve.
I havent taken amour but have found other NDT’s (thyroid S;Naturethroid; Acella) about 1 grain close to 100 mcg Levothyroxine, but obviously much better because of the T3
You probably need to give it more time before raising again.
That said I never did well on Erfa even though i really wanted to, but do fine on combined T4+T3. I like that i can titrate each individually.
It's very confusing I know. Wish it was easier!
I see in a previous post T3 didn't work for you either. Makes me wonder if there's something else going on eg
- High/Low cortisol
- Pernicious anemia / Functional b12 deficiency (serum levels look ok but you still have symptoms of low b12) . Pelvic pain could be a sign. b12deficiency.info/signs-an...
- Hypo/hyper-parathyroid
- Have you posted iron (& other) labs here lately? Few days ago i was thinking my iron levels aren't all that bad, then on my exercise post someone asked for the actual levels, and only then did i realize they had fallen much more than i initially thought. Despite doing this for 15 years 🤦♀️
Thank you for your input! Just recently measured blood calcium levels, it was good, so I take it parathyroid is working well since it manages it. Yes, at a time of me taking synthetic T3, I had slightly high cortisol am and noon, normal eve and night in my saliva test and I was taking herbs and doing things to lower it. But higher cortisol was triggered by levo over medication symptoms. I haven't measured my adrenal saliva since Feb and we are away now to do it again. But I feel tons better. In saying that, I had no problems switching to T3 in NDT and my BP and pulse has not been affected by upping up to 1 1/4 grains in 2 weeks. This makes me think it was synthetic T3 that was an issue for me. I read some people couldn't tolerate it either, but did well on NDT.
That sounds promising. Probably just need to give it more time. I vaguely remember you should wait about 2 weeks between raises and hold 6 weeks at 1.5 grains & test.
For Parathyroid , sounds like yours is ok. If calcium is doing strange things (too high/low), they can test parathyroid (PTH blood test). I am not sure how much it directly affects thyroid med tolerance, but i wouldn't be surprised if it did.
Sorry to hear that you are having problems titrations your dose. I can’t offe4 any advice because I’m not as knowledgeable as most most on here. I’m replying because I’m also struggling with Erfa. The math confuses me as well. 60mg could not possible be equal to 100 levo. I’m a poor converter and was taking levo + cytomel prior to starting Erfa. I have struggled with titrations my dose from the very beginning, but decided to stick with it. I have most of the symptoms you described and my vitamins are all good. I’m presently taking 75 Erfa + 50 levo. Just started three days ago and is feeling slightly better with the increase of levo. I was taking 90 Erfa + 25 levo, it was not working for me ( fatigue, head pressure, sleep disturbances, low mood, weight gain and many more) my t4 only 20% in range, t3 @ 56%. When I test in 6-8 weeks, if there is no improvement I will ask to return to levo + cytomel. So very frustrating! This thyroid disease leaves us feeling defeated and with low quality of life.
We should all be thankful for this forum! A place to vent and receive good advice
Thanks to the lovely people that give of their time and knowledge, even though they’re suffering as well.
Oh I only followed the dosing guide and never stopped for a week - I didn’t even know that was suggested and wouldn’t advise anyone to do that. It might be adrenal stuff which I don’t bother with as it seems a nebulous area to me. You seem to have a big downer on the whole thing. I found it helpful and better than STTM.
The tritrating protocol worked really well for me and that was what I pointing to. It sounds like it is what medics were taught when NDT was the only thyroid replacement hormone (bar T3 which I think was used later on)
I still think a mercury thermometer is the best but I’m from a different era I don’t trust my digital one it gives very variable readings - I suspect it’s faulty or my temperature gauge is doing sommersalts. I know they are dodgy things tho cos of the Mercury and needed to be got rid of.
What’s the freezing point about?
It’s has become stranded in time I agree as I don’t think the site has been touched in years but the dosing bit remains reliable, or at least was for me, despite the passage of time.
I know some people have frozen some desiccated thyroid and found they ended up with an unusable sludge.
Even if that doesn't happen, water molecules move around. I mean, we often see a layer of ice crystals with frozen food packaging, which demonstrates it happens. But thyroid hormone is extremely sensitive to having its level of hydration changed.
I'd avoid freezing. I'd avoid refrigerating if it goes below about 5 C. And I'd avoid doing so in an auto-defrost refrigerator or freezer because they can see substantial temperature swings. Especially for small items like tablets!
And any refrigeration at all needs absolutely air and water tight packaging.
Ah yes that’s a good point. I’ve never frozen any but do keep mine in a fridge…oh dear I upgraded to an auto frost model about 6 months ago so alarming to read your advice there. My flat gets really hot in the summer so it’s the only reliably cool place I have. My NDT is out of date by a year now I got a bit too much in a panic buy when supply was looking dodgy, but still seems to work ok much to my surprise. I wish we could get it on the NHS if that’s what we find best to control symptoms but I can’t see it happening in my lifetime. I think I’d top myself if I had to go back to T4 monotherapy, it was that awful.
Big things (frozen portion of soup!) - no problem. Small things can defrost and even rise substantially in temperature. They then rapidly cool down again. So you can easily not notice the temperature cycling.
even in the fridge bit? Sounds like a health hazard to me I had no idea they worked that way is the whole caboose working in concert then? Clever but not so clever?
The defrost mechanism in a refrigerator heats the cooling element (evaporator coil) for a short period of time and melts the frost that has formed on it. The resulting water drains through a duct at the back of the unit. Defrosting is controlled by an electric or electronic timer: For every 6, 8, 10, 12 or 24 hours of compressor operation it turns on a defrost heater for 15 minutes to half an hour.
The defrost heater, having a typical power rating of 350 W to 600 W, is mounted just below the evaporator in top- and bottom-freezer models and below and sometimes also in the middle of the evaporator in side-by-side models. It may be protected from short circuits by means of fusible links. In older refrigerators the timer ran continuously. In newer designs the timer only runs while the compressor runs, so the more the refrigerator door is closed, the less the heater will be on and the more energy will be saved.
A defrost thermostat opens the heater circuit when the evaporator temperature rises above a preset temperature, 40°F (5°C) or more, thereby preventing excessive heating of the freezer compartment. The defrost timer is such that either the compressor or the defrost heater is on, but not both at the same time.
Inside the freezer, air is circulated by means of one or more fans. In a typical design cold air from the freezer compartment is ducted to the fresh food compartment and circulated back into the freezer compartment. Air circulation helps sublimate any ice or frost that may form on frozen items in the freezer compartment. While defrosting, this fan is stopped to prevent heated-up air from reaching the food compartment.
Oh, do we need to keep it in the fridge? I never put mine there, or my old levo. Is it better to? I am sure most people don't keep theirs in the fridge.
It was a discussion largely about why NOT to store in a refrigerator or freezer.
However, if your home is reaching more than 25 C, regularly, and your only alternative is your refrigerator, it is an understandable approach. But read the link below first:
Very helpful to read and exactly my story too! Whenever I added more levo than what I was on, over-medicated symptoms with heart palps, high pulse, high BP (to a point of going to A&E!) but still high TSH. So I get it.
I can see NDT does not translate to levo well. 88mcg should be 1 grain, in theory, but in practice you started to feel better on more than 2.
You were increasing much faster than me, from 1 to 2 grains in 1 week. I have been on it for 2 weeks and only up to 1 1/4 grains. Throat is still sore, so need more. I will up it to 1.5 grains and see from there.
Thank you again, we were taking the same levo dose before, so very helpful!
I’ve been on NDT for about a year - you need to stick at it to find your optimal dose.
My Ths is completely suppressed as I’m taking NDT, so to be expected. My T3 and T4 are exactly where they should be and I feel good. I started on 2.5 grains ( my doctor’s recommendation ) but it was a bit too much ( my t3 was slightly over). I find the dose I’m on now is working for me. I’m so glad I switched- I realise now how awful Levo made me feel.
I also have made sure my D3 and B12 levels are optimal so I take supplements. I also take NAC . I make sure I take 4 Brazil nuts a day and I take magnesium glycinate and inulin before bed for sleeping.
I have Hashimoto’s- so all the above are important. I am not gluten or dairy free, but my current protocol works for me.
Thank you for the reply! So your current protocol has helped you reverse high antibodies and yours are totally good now? I tried taking NAC, but it gives me a headache... I know it is useful with Hashi though.
I think it is pointless trying to compare these 2 totally different treatment options.
1 grain Efra contains trace elements of T1, T2 and calcitonin + 8 mcg T3 + 35 mcg T4 :
T3 is said to be around 4 times more powerful than T4 - and our body runs on T3 not T4 :
It takes around 6-8 weeks for the Levothyroxine to slowly leave your body and in that time frame as the synthetic medication reduces in your blood stream we slowly build up the NDT to hopefully create as smooth a transition as possible.
5 days ago on 1 grain you had a wonderful day - maybe stay on this 1 grain for a couple of weeks and let this dose settle in your body.
What dose of synthetic T3/ T4 did you settle on and how did that suit you ?
As Hashimoto's have you checked for celiac, and first healing the gut, food intolerances etc - thyroidpharmacit.com
As detailed previous we need optimal levels of ferritin, folate, B12 and vitamin D maintained for any thyroid hormone replacement to work well or us.
As detailed previous having Hashimoto's throws a spanner in the works as you are liable to experienced erratic own daily thyroid hormone production.
Trying to explain things like that in an accessible form is very difficult.
My main aim was to say that a simplistic formula (something like "T3 is four times as potent as T4") leads to poor decisions and understanding. But I had to try to explain WHY that is the case.
I got it from Tania Smith that people make hugely varying amounts of t4/t3 and the thyroid can produce T3 almost exclusively as the thyroid dies but this helped in envisaging the t4 to t3 conversion variables at play.
I find it odd that people can seem to talk about NDT as if it is T3 only, yet most of it is still T4.
The dynamism of it is lost with these static numbers trotted out as fact.
"So if I was on 88 McG of levo before NDT and I now take 1 grain of NDT instead, I only get 38 McG of T4?"
The" standard" equivalency charts estimate each mcg of T3 in Erfa is equivalent to 8.1 mcg of T4, so they're estimating that you are getting the equivalent of 88.4 mcg of levothyroxine.
So if you were already "hypo" on 88 mcg of lego, this probably wasn't an improvement, especially if your FT3 levels were low. The rigid rules also don't account for how different people metabolize their thyroid hormones.
An equivalency study suggested a 1:3 substitution ratio.* This would suggest 1.5 grains of Erfa to get to your 88 mcg Levo dose. That would be providing 51 mcg T4 and 12 mcg T3.
All of this is moot if your doctor won't test Free T3 levels and relies on TSH.
Patti in AZ
*Equivalency study (2010) ncbi.nlm.nih.gov/pmc/articl... Rare study with subjects without a thyroid and split dosing 3x/day.
This is so useful, thank you so much! My functional MD said that 1 grain is about 75-100 mcg of levo, I was hoping it would be enough, but this is not accurate at all for me. I've actually upped up to 1.5 grains today as my BP started to dip and I was waking up feeling numb in my hands, which is a sign of being undermedicated for me. But overall, I feel ok energy wise now, though time will tell.
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If calcium is doing strange things (too high/low), they can test parathyroid (PTH blood test). I am not sure how much it directly affects thyroid med tolerance, but i wouldn't be surprised if it did. 
Please can you advise me on my calculations to switch NDT to Levo
NDT Users - Split Dosing
fT4 dropped from 16.4 to 8.3 after starting trial of NDT? 
