Thyroid UK
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Erfa (or any NDT) overdose advice

Hi thyroid-gurus,

I put up a post yesterday about over-doing it on Erfa. Basically, I thought I might be overdosing on 2 1/2 grains as I had onset of symptoms like diarrhea, nausea, aches, muscle pain, headache and awful fatigue. Today I just took 1/2 grain and the symptoms not only persist but got worse for about 5 hours. Haven't taken any since and I'm now looking for advice on what to do once you suspect you are overdosing NDT? Do you stop taking it completely for a while to let the levels drop, or do you have to reduce the dose slowly to prevent a similar bad impact?

Any advice would be much appreciated if you've experienced the same problems with upping doses.



7 Replies

It takes about 2 days for the blood level of T3 to go down. Unless your problem is from a virus or food poisoning, you should be getting better tomorrow.

The ratio of T4 toT3 may be problematic for you. Possibly taking 1 grain of NDT and taking T4 for the balance, like maybe 75 mcg T4 or 62.5 mcg T4 would be a good place to work from.


Just wondering is 1 grain equal to 60 mg NDT = 75mcg t4?

I'm taking 120 mg NDT and feeling rubbish. Doc suggested I add in T4 but I read on STTM that combining can cause RT3 problems. Any thoughts?

Have been on it about a month an stacking on weight but then it started back when I was on 150 mcg T4. Don't know which way to jump.




Jayne22, according to Nature Throid's website for instance,

1 Grain (65 mg) = 38 mcg T4, 9 mcg T3


Thank you x


Hi It is important to have a blood test TSH, T4 and FT3. the only way to tell. I was overdosed on armour by a private doctor, more I had the iller I felt. It turned out I was hyper with the same symptoms as hypo, by over dosing.. If i had had bloods done I would have avoided the dangerous results.Safer to under treat than over.



What is the batch number and expiry date of your ERFA?


Thanks everyone. I'll be getting bloods done soon to check on it all.

Hypopotamus - batch # LF03139A, expiry 31/10/2016.


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