Avatar universal

Why do I feel hypo?

Dear all,

I feel off and I suspect it's my thyroid.
I'm taking NDT (Erfa) 2 grain + 12,5mcg Cytomel a day.

TSH 0,01
FT4 11,82 (ref: 9,0 - 19,0)
FT3 4,60 (ref: 2,63 - 5,71)
RT3: 32,9 ng/dL (ref: 9,0-35,0)

Why do I still feel off ?

Gr Jeff
6 Responses
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1756321 tn?1547095325
My sweet spot for free T4 is 16 (10 - 20 pmol/L).
Helpful - 0
Hi Red Star,

Thanks for your comment.
You might think I'm getting to less T4 right ?
Now taking 2 grain + 12,5 t3. Do you think the large t3 I daily take (16 in my Erfa + 12,5 Cytomel) could be the cause ? Or is this dose not high enough for that the be the cause ?

Gr Jeff
Avatar universal
I assume that you are taking two 60 mg ERFA tablets to get two grains. One 60 mg ERFA tablet contains 38 mcg T4 plus 9 mcg T3, two tablets give you 76 mcg T4 plus 18 mcg T3, and if we add on the 12.5 mcg Cytomel you are taking a total of 76 mcg T4 plus 30.5 mcg T3.

There are two possibilities why you are not feeling quite right: (1) something isn't quite right with your thyroid meds, or (2) there is something other than your thyroid that is not quite right. You definitely should not discount the number (2) possibility, but I'll assume that you have ruled that out. So what could be wrong on the thyroid side?

T3 is the active hormone in your body and your FT3 level looks fairly good at 64% of its reference range. However RT3 is high, at the top of its reference range. So the amount of RT3 is higher than normal in relation to the amount of Ft3 that you have. For the sake of argument let's say that the midpoint of the RT3 reference range (22.0) is "normal", then your reading of 32.9 is 1.5 times normal. RT3 is believed to act as brake on the action of FT3, so even though you have a normal looking amount of FT3, the RT3 may be acting as a damper on its ability to function properly and the result would be that you feel hypo.

So why would your RT3 high? here is the explanation in point form:
You take 76 mcg T4.
T4 is converted to T3 and RT3, usually in approx equal amounts.
You take 30.5 mcg T3, which is a relatively high dose.
Your body has a built in mechanism to prevent your T3 from going too high (hyper), as follows.
The more T3 you take, the less T4 needs to be converted to T3.
The less T4 is converted to T3, the more T4 that has to be converted to RT3.
So it appears that if you take 30.5 mcg T3, you don't need as much as 76 mcg T4 in order to get the amount of T3 that your body wants.

What to do? You probably found that you were hypo with only two grains NDT (76 T4 + 18 T3), so you added the 12. mcg cytomel. I think one possibility would be to cut the cytomel to 5 mcg. That would allow more of the T4 to be converted to T3 rather than RT3. It sounds like a small change, but I think you would find the change significant.

Another possibility is to go to synthetic compounded T4 and T3 which gives you complete flexibility in the amounts of T4 and T3 you take. This is why some people go that route.

Hope you can follow this...
Helpful - 0
Hi Telus2,
Thanks for your reply and expertise.
Would it be a solution to drop the erfa even more and add more cytomel? Would the rt3 drop aswel and wouldn’t I be out of me hypo-state? Gr Jeff
Hi Jefj,
I am thinking about your question. In the meantime, do you happen to have lab tests on 2 grains NDT only? Or 2 1/2 grains? If so could you pls post the numbers, including ref ranges. Thanx.
Avatar universal
You might be interested in possible causes for excess conversion of T4  to T3.  If you click on my name and then scroll down to my Journal, you will find a one page Overview and a link to a paper on Diagnosis and Treatment of Hypothyroidism: A Patient's Perspective.  In Recommendation 11 on page 12 you will find the following info.  

In addition to the effect of stress and related high cortisol levels, "Other postulated causes of reverse T3 dominance include a broad spectrum of abnormalities such as: “Leptin resistance; Inflammation (NF kappa-B); Dieting; Nutrient deficiencies such as low iron, selenium, zinc, chromium, vitamin B6 and B12,   Vitamin D  and iodine; low testosterone; low human growth hormone; Insulin dependent diabetes; pain; stress;   environmental toxins; free radical load; haemorrhagic shock; liver disease; kidney disease; severe or systemic illness; severe injury‟, surgery; toxic metal exposure”8.4

So if you are aware of any deficiencies among this list, then that is a place to start.  Beyond that, I have found that in a similar situation I was successful in reducing my RT3 level by reducing my T4 dosage, in order to reduce conversion to RT3.  I also slightly increased my T3 dosage.  
Helpful - 0
Hi Gimel,

Thanks for your comment. I appreciate the time you took for you to help me. That's what I did. Decrease T4 and slightly add some t3. But by any means, I'd really like to find out what the root cause is of the high rt3. I did not figured that out yet. Which is frustrating. To be honest, I haven't got a clue where to start searching. My iron levels are good, b12 was kinda low but supplementing now, adrenal should be fine is I'm feeling quite good while I know the feeling of adrenal fatigue quite well. If I see your list of possible causes I can't help feeling discouraged. The list is so long and half of it I haven't even heard off.

I'd love to fix my RT3 for good and be able to just take my erfa like I always have done with great results before. Don't know where to start investigating for the root cause.

Talk to you soon,
Avatar universal
Here are my thoughts on your question, "Would it be a solution to drop the ERFA even more and add more cytomel?

Yes, you could get to a solution that way. If you carry that solution to an extreme, you would drop ERFA altogether and just take T3 (cytomel) and indeed some people have done that with good results. But I wouldn't suggest that you decrease your ERFA.

This is why I say that:
1. I believe that you are quite close to having a good dose and only require a small change.
2. It's good to take some T4 because it stays in your body longer than T3 and acts as a reservoir that can be converted to T3 as your body requires it. When you consider that a normal thyroid gland produces 90-100 mcg of T4 daily, your 76 mcg dose is not excessive at all.
3. As you are close to your optimum, it's better to take small steps and change one variable (T3) at a time rather than two (T4 & T3).

One thing you did not indicate was whether you split your daily dose into two (or more). If you do not, it is quite possible that simply splitting the dose could reduce your RT3 - this is because the T3 you are taking causes a rise in your FT3 in the first 4 hours after taking it. If you split your dose, the peak of that rise will be lower. That would help even out your FT3 thru the day and might make the RT3 lower.

I would try splitting the dose and 2 grains NDT + 10 mcg cytomel.
Otherwise try split 2 grains + 5 cytomel.
Helpful - 0
Hi Telus,

Thanks for your answer once again.
I do not split dose. I'm taking everything all in once first thing.
I understand your point very well.

Would you split dose Erfa or only cytomel ? Or both?
I always felt good with one dose and also feel very sad knowing I'll have to split dose and watch out at noon everyday to take it. Also it's very inconvenient to manage it away with food at noon.

Gr Jeff
Avatar universal
Yes splitting the dose is a royal pain on the posterior, but if it takes you from "feeling off" to something better, then it's worth it. I would split both. You could maybe go 1 grain plus 5 cytomel each time for starters.

This is how I split mine: don't eat after 8-9 pm in the evening and take half at bed time 10-11 p.m.; finish breakfast before  9 a.m. and take half at 11 a.m. and your good to eat lunch at noon.

Helpful - 0
Hi Telus,
I've started splitting the Cytomel dose to twice a day. One in the morning with full dose of Erfa and once at noon. I've heard Cytomel can be taken with or without food, which makes it easier to take at noon as I don't quite have to watch out with my lunch. Is this true ?

So I've split my dose in twice 6,25 mcg t3 a day with 2 grain in the morning. Hope this alone can drop my RT3 to a better ratio.

Will check blood in 3 weeks to see if this is working. However I'd love to find out the root cause of why RT3 is climbing in the first place. Do you think the large t3 I daily take (16 in my Erfa + 12,5 Cytomel) could be the cause ? Or is this dose not high enough for that the be the cause ?

Talk to you soon, Jeffrey.
Avatar universal
I have rec'd your message. Could you please explain what hypo symptoms that you are having and how severe they are.

You are considering changing from 2 grains NDT plus 12.5 mcg Cytomel (76 mcg T4 plus 30.5 mcg T3) to 2 1/2 grains NDT (95 mcg T4 plus 22.5 mcg T3). That increases T4 and decreases T3, so it is hard to say what it will do to your RT3.  2 1/2 grains NDT is still not a very high dose, so it might be worth giving it a try. As you are changing your T4 amount, you will give it enough time (4 - 6 weeks) to see if it will work.

What is your procedure when you get lab tests? It is recommended that you get tests done in early morning and do not take your meds in the morning before the lab tests.
Helpful - 0
Hi Telus,

Thanks for your answer.

I've changed to 2,5 grain yesterday. No Cytomel.
We'll see what this brings me regarding rt3.
Supplementing with b12, iron, D. Hope this will bring my RT3 in check.

I do get blood tested in the morning prior taking meds.

Gr Jeff
would your doctor consider adding a t4 med? what are your hypo symptoms?
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