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Started NDT- getting angina symptoms and palpitations early morning- T3 to blame?

I have now started NDT (Naturethroid) half a tablet (equivalent to 50mcg Thyroxine) together with 100mcg of Thyroxine. I feel less of an urge to go running (was that my way of elevatiing my T3 on T4 only?) and calmer. However, after 2 and 1/2 weeks I'm now waking with a pounding heart and last two days have had what I think is angina (tight chest, tight throat, like really bad indigestion). I have been taking iron supplements but I imagine not rising quickly. Before starting NDT my levels were as follows:

Ferritin 23.30 (range 10-300)

B12 440 (range 200-950)

Iron 86 (range 50-170)

Vit D 34.90 (range 30-100


Folate 15.27 (range 3-20)

My question is: is it the T3 that needs higher iron because only T3 acts on the heart muscle, and the heart only has T3 receptors? Could it be that the angina is caused by my still low ferritin levels?

Has any one else experienced angina or palpitations in the early morning as a result of NDT?

And does any one have a suggestion of what I should do next? The angina is pretty scary!

9 Replies

Could be low magnesium? (Goggle symptoms)

Also your vitamin D is low. Are you supplementing?

B12 and ferritin look low too.


Hi there Slow Dragon- I'm supplementing magnesium big time

1 like

B12 needs to be around 1000. I had angina type pains on starting Levo ,mostly sorted with beta blockers .


Hi Treepie- Did you have to sort out your B12 as well, or did you also have an underlying or pre-existing heart problem?


B12 was just below 500 so I supplemented. A book by a GP I was lent referred to angina pains following starting on Levo being easily treated with beta blockers.

I think Levo speeds up the metabolism and leads to blood flow problems if there are obstructions.I had ultrasound and angiogram and was told my veins were "irregular" !

No heart problems .


That's very interesting, thank you! Are you still having to take beta blockers, and do they have any side effects?


I have had to increase the amount of beta blockers I am taking over the past year. I have no side effects but I am rarely affected by medicines. I take them at least four hours away from the Levo. I have read that some beta blockers affect conversion of T4 to T3 but that may not be a problem on NDT.

Just recalled the author of the book I mentioned: Joan Gomez,but it's a very basic old book.


Half a tablet of nature thyroid is more like 35mcg levothyroxine

I would be more suspicous of the actual levo causing palpitations than the t3 in nature thyroid


Hi reallyfedup! The Nature Throid conversion table says that half a tablet of Nature Throid is equivalent to 50mcg of levothyroxine, but I've seen else where on this forum it's not actually an accurate conversion. Interestingly, the Nature Throid seems more powerful than thyroxine, in that I've now reduced to one half tab Nature Throid and one 50mcg of thyroxine and feel well- though too early to say if it will last (used to be 150 mcg of Thyroxine). No angina or palpitations so far. Also read the leaflet and Nature Throid states that angina can be caused by overdosing.


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