Switching from Levothyroxine to NDT: I've just... - Thyroid UK

Thyroid UK
110,150 members128,042 posts

Switching from Levothyroxine to NDT


I've just received my NDT Thiroyd from Thailand. Can anyone help with how to make the switch. Do I just stop Levo and start on 1 grain of NDT? Or do I reduce Levo gradually and increase NDT gradually. Both tabs are small and would be difficult to split I imagine. Can anyone help please.

19 Replies

Check out the STTM wesbite, it gives lots of advice on making the switch x

HiddenThis reply has been deleted
Rita-D in reply to Hidden

Thanks reallyfedup. I've tried searching on there, but couldn't find it. I'll try again.

Hi Rita-D

Let me know how you get on. I have taken my first dose of nature throid today. I grain. I was previously on 100 mcg of Levo and 25 mcg of t3. Last dosage yesterday.

Hi leanne2410, that's what I have done. I was on 100 mcg of Levo only. My last dose was yesterday too. I have previously tried Levo and T3 and T3 only (had massive fluid retention on T3 only). Just hoping that Thiroyd helps.

leanne2410 in reply to Rita-D

That's one of my issues bloatedness to the point where I look pregnant bad stomach cramps and water retention to name a few!!! Hate levothyroxine!!! Good luck. X

Clutter in reply to Rita-D

Rita-D, 1 grain NDT is bioequivalent to 75-100mcg Levothyroxine. You can switch to 1 grain the day after your last dose of Levothyroxine. Dose can be increased in half grain increments fortnightly. Hold at 2 grains or 6 weeks and have a thyroid test including FT3 before increasing dose further.



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.

Rita-D in reply to Clutter


Thanks for the information.


You do a straight switch-over. It depends on what your dose of levothyroxine was. For instance if you were taking 100mcg of levo, that's equivalent to 1 gr of NDT. and if it was 150mcg of levo it's 1 1/2 tablets.

Rita-D in reply to shaws

Thank you.

I am on 100mgs of Levo, so I've taken 1 gr of NDT today. Hope this works!

shawsAdministrator in reply to Rita-D

Stay on this dose for 2 weeks and then increase slowly (I'd do a 1/4 tablet at a time - some do 1/2). Take note of your pulse/temp several times today. Preferably it should have been before you begin. It's a way to judge, i.e. if your pulse temp were low (usual) in hypo, both should slowly become normal. If too fast or too hot you'd have to reduce to previous dose or miss a day's dose.

Rita-D in reply to shaws

Thank you for the advice. I'll do this.

I changed to Thiroyd from levo gradually and yes cutting tablets was a mess I couldn't get two exact halves so was a nuisance for me. But I think some people stop levo and go straight on to NDT, just depends how you feel about it. Trial and error and everyone different!:)

Sure you will be OK however you make the change.

BTW I had swollen ankles and feet on levo and it all cleared up on NDT.

Rita-D in reply to win_4ever

HI win_4ever, I'm going to try a straight swap as advised by Shaw. I had swollen ankles, hands and feet on T3 only, so I'm hoping that NDT works for me.

Thanks for replying to me.

Boon79 in reply to win_4ever

Sorry, I appreciate this thread is old, but I am on 100mcg of levothyroxine and have just ordered thiroyd from Thailand. Should I start on 50mcg of levothyroxine at night and maybe half a thiroyd tablet in the morning? Thank you

Rita-D in reply to Boon79

Hi Boon79, sorry I can't help you with this. I spent nearly a year trying to get optimal on NDT and was not successful - just could not raise NDT and got gradually worse over that period of time. I suggest you follow what others have said on this thread and make sure you have no problems with your adrenals (which seemed to be my problem). Good luck.

Personally I stopped levo for 2 weeks before starting a low dose of NDT. Levo can stay in your system for 7 weeks. Start on a low dose of NDT and build up over a few weeks. I was gobsmacked at how much better I felt even on a low dose.

Hi, I'm new to this website and trying to understand the threads. I have been on levothyroxine 100 mcg for ten years. I regularly have a hoarse voice, always tired and have piled weight on over the years. Despite constantly calorie counting. I have an annual review and bloods done and assume it's all 'normal'. However reading the threads on here many people are talking about changing their medication, excuse my ignorance but how do you know this will make a difference?

You may also like...