Thyroid UK
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How long after stopping NDT back to "normal"?

I was in "normal" T3 range (4,82 pmol/L ref. 3.59-6.8 pmol/L). I decided to try for 45 days NDT. I came to 2 grains daily dose which gave me T3 on top range and TSH 0.04 (ref. 0.55-4.78). But I don't feel anything better and all hypo symptoms remains.

Now I think it it possible the problem is not about thyroid but about testosterone which is also low, DHT (which is another anabolic hormone and is too low) and about adrenals. So I decided I will rather try testosterone replacement theraphy with adrenal support and see if I see any difference.


If I stop NDT right away after being on 2 grains daily dose. How long does it take that thyroid goes back to where it was before starting NDT?


9 Replies

Confused85, It may be better to hang in at 2 grain for 2 or 3 months. Symptoms can lag behind good biochemistry by a couple of months.

T3 will be out of your system roughly 3.5 days after last dose. The long half life of T4 means you will have 1 grain in your system after a week, 1/2 after two, 1/4 after 3, so most will be out of your system within 4 weeks.


I am not a medical professional and this information is not intended to be a substitute for medical guidance from your own doctor. Please check with your personal physician before applying any of these suggestions.


Have you had testosterone tested ???

What is your level ?

Do not try testosterone until you have tried progesterone. It is very good for men. Google the steroid hormone cascade and look at the diagram of how the starter hormones break down into more powerful ones.

Thyroid will also raise your testosterone, but so will progesterone if used in moderation for a male (max 10mg per day).

Best to use ray peat ProgestE product as 1 drop = 3mg.

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I apologize for late response. My testosterone level is around 5 (ref. 2.18-9.06 ng/ml), but free t has been low 8.4 (ref. 3.84 - 34.2 pg/ml). Also DHT is low 297 (ref. 300 - 850). SHBG is at top range 40 (ref. 14.7 - 44.9nmol/l).

This is why I think that it would be better idea to try testosterone and stop with NDT for now because my SHBG was already at top range. One of the side effects of thyroid tablets is that they make SHBG even higher. And my SHBG has been already high before taking it. In my scenario NDT could possibly make DHT and free t even lower.

Adding some testosterone can improve DHT and free t and it would support adrenals to use T3 more efficiently.


I agree with Clutter, also it takes time to work up to 2 grains, probably more than two months, as with NDT you hold the raises incrementally. Also seeing as you were already not bad on T3 before you started, not sure that was the correct dose. Also, you then also upped your T4 ...

Are you a body builder, are you trying to get lean?

Also be very careful with Testosterone. Are you taking another other hormones or supplements?

This can artificially affect testosterone levels.

Also too much T3 increases you SHBG which affects your levels of free hormones


PS not sure a man should ever take megadose progesterone!!


OF course not, but 10mg is not a mega dose. A man and a woman make approx 20mg per day. Women will then make more at different times of her cycle.

So 10mg for a man per day is the recommended maximum to take. Much better to use the progestE product which gives you 3mg in one drop. I only use 3mg per day, but it is very helpful to my steroid hormone production.

Progesterone in large doses is used to treat sex offenders, but in small doses it can be very helpful. Especially for prostate health as we get into our 50's


I am not budybuilder or trying to get lean, I had all hypo symptoms (low temperature, dry skin, no energy, no libido) and this is why I decided to try NDT. No other hormoney. I am aware about SHBG, this is why I will probably stop NDT because my SHBG is already at top range which lowers my free T (see my answer below).


Ah I just tired to answer this and then it wouldn't let me post, and I think you've edited in between me getting the alert and trying to reply. Here's what I wrote, am rushing so sorry, realise you just answer the hypO bit x


I confess this is out of my area really, hormones are incredibly complex, and I'm female (!!), but I'm deliberately TSH suppressed as I had thyroid cancer, and take - deliberately - a little too much thyroid to keep my TSH undetectable. Therefore my SHBG is higher in the range, although not so bad now that I'm on less thyroid meds (whilst still keeping TSH low) which caused issues with my estrogen.

Also I stupidly - a while ago now - did a regime for adrenals which required Hydrocortisone, and HC can tank testosterone, so I ended up on a low dose androfeme gel for women with low T. It did help, but my body really was out of balance. I did take progesterone as well for a while but that stuff converted to cortisol in me, and often does in people- if you look at the conversion pathways, it's not as simple as put one thing in, and you get more of that one hormone, things can go awry (which is our major gripe with hormone doctors in general, as the often blithely stick people on HRT or whatever in this one size fits all approach).

My own experience, and this is just for me, is I'm now full circle and trying to figure out WHY I am still unbalanced (so I'm low P and high E at last test) rather than jump straight to hormone replacement.

You didn't say whether you actually had a thyroid problem, I assume so, but this woman writes a really well researched site with lots of scientific references, she's a patient who just got frustrated with a lot of partial information around for thyroid patients so put it all together herself, after getting in a pickle following some protocols she picked up online (so did I!!) - she wrote a section on low T for men which might help you or at least going in the right direction. I don't fully agree with all she says on her site, but it's one of the best I've found, and her book helped me a lot too.

The reason I asked about the body building is a lot of those guys, particularly when getting cut for a competition, will manipulate hormones to build muscle and drop fat but I'm not sure it's a particularly wise or safe idea. Just my tuppence worth!

Hope you figure it out




A pharmacologist friend told me they consider 10 half-lives to be the time it takes a medication to be completely gone. So for T4 that will take you to 60 days.

The usual rule of thumb is that you need to be on a particular thyroxine dose for 6 weeks for your body to settle and see the benefits.


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