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Need A Reliable T3 Source - Please Help

Hypo for many years. Still symptomatic. Currently on 200mcg Levothyroxine plus 20mcg T3. Non existent TSH <0.01 mU/L. Endo wants to get my T4 & T3 up but proposes doing so by increasing T4 only. Not willing to increase T3. Recently confirmed privately I have the DIO2 gene plus high reverse T3 so I want to switch to T3 only as this is the only thing that will help me. I need to find a reliable source of Mexican Cynomel asap. Please PM me if you can help.

Most recent results:

TSH <0.01 mU/L (0.35-5.00 U)

Free T4 15.9 pmol/L (9.0-21 U)

Total T3. 1.6 nmol/L (0.9-2.5 U)

These results have been flagged up by the lab as **ABNORMAL**. Can't get FT3 done. There isn't even an option on the computer at GP for TT3. Has to be a special request.

Pretty sure I have Hashimoto's but has never been confirmed. I need to find a reliable source of Mexican Cynomel asap.

15 Replies


The DIO2 impairment does not mean you need to take T3 only. The 20mcg T3 you are taking with Levothyroxine should overcome poor conversion. You can reduce high rT3 by reducing Levothyroxine dose and increasing T3 dose for a while.

Your labs are flagged as abnormal because TSH is suppressed below range due to the high doses you are taking.

If you want antibodies and FT3 tested you can order your own blood tests via thyroiduk.org.uk/tuk/testin... Medichecks offer #ThyroidThursday discounts.

If members can recommend sources they will send you a private message. To read a private message: support.healthunlocked.com/...

To send Hyburn a private message: support.healthunlocked.com/...


Thanks @Clutter for your helpful response. Lab used to say 'Low TSH unlikely to be clinically significant in the absence of toxic symptoms'. I don't know why their view has changed. Endo I see now says she would not have put me on T3 but so far is still keeping me on it but won't increase the dose. I don't think she should increase my T4 in the light of my results.



rT3 isn't tested on NHS so probably isn't seen as useful so your endo probably doesn't even get training about rT3 at med school.

You could swap 37.5mcg Levothyroxine for 12.5mcg T3 but you will need to check that FT3 remains within range.


Suspect you might have vitamin issues if you havd Hashimoto's

Have you had vitamin D, folate,ferritin and B12 tested

Definitely get antibodies tested

Have you tried gluten free diet?

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Have been gluten free for ages thanks as coeliac disease also runs in the family. I am prescribed Vit D by GP as it was low, folate is low end normal, ferritin was ok and Medichecks active B12 test showed it was too high and recommended to check liver and kidney function which were okay. Been meaning to pursue getting antibodies checked. Will ask endo about this next appt. Have vague memory of being told it doesn't matter as I am being treated for hypothyroidism anyway!!!

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Suggest you read The Thyroid Pharmacist website

Medics ignore Hashimoto's, patients on the other hand find they need to understand it, to get to root cause

What level is vitamin D and are you only taking 800i. If so likely to still be too low. Vitamin D level needs to be at least at 70nmol but around a 100 might be better

Coeliac often low in magnesium. Also good idea to take magnesium if supplementing vitamin D


If you have not been supplementing B12 and it's high that suggests something going on.



You could post on PAS Unlocked that you have over range B12 and low folate. They are the experts on B12

You might want to get active B12 test - NHS very reluctant to ever do this. Medichecks or Blue Horizon both offer it

Ferritin "ok" needs to be at least half way through range

Low stomach acid is often a problem, and or gut infections



I have the Dr Izabella Wentz book 'Root Cause' though it is a while since I read it.

Vit D has not been tested since I went on to Colcalciferol 800IU in April 2016. Lab refused to do it as it was a 'repeat request' and said previous result was valid for 340 days!!!! It was 26nmol/L on 27.04.16 (I posted this on a message recently - think it was to you but not sure). Can see I am going to have to rattle a few cages from now on.

On 09.02.15 my Serum Vit B 12 was 617ng/l (200-900); Serum Folate 5.1 (3.1-20); Serum Ferritin 140ug/l (15-200). As these were done more than two years ago I will be asking to have them done again.

Recently had Medichecks look at Active B12 which was 194.8pmol/L (25.10-165) This was flagged as too high and they rec decreasing dose if I was supplementing and, if not, to have FBC and liver function checked which I did and all came back normal. (I have said this before too but did not give the actual figure for B12.)

What do you think?


If you can't get GP to check then suggest you use Medichecks again

Just Vitamin D on its own, then £28 test is cheapest

I had similar too high B12, (never supplemented) but had vitamin D deficiency. When I started high vitamin D supplements, few weeks later was getting increasing peripheral neuropathy (due to low B5)

This article prompted me to start B complex


Starting Vitamin B complex then caused pins & needles few days later - I assume was low B12. Adding sublingual B12 soon improved it

Apparently B vitamins have to all work together. If one is 'missing" then the others sit around. This might (or might not) be the cause!


Do have some tingling in fingers and toes from time to time so will look into this SlowDragon. Thanks for the input. Will need to make lists and lists of things to do.


Vitamin D level is key

Your previous test was very low at 26

You should have been given a loading dose by GP

If you have only ever had 800iu it's likely still low

Very common - loads of people arrive here in similar situation

Look up your local CCG guidelines on vitamin D. Each CCG area has slightly different treatment guidelines


Don't think we have CCGs in Scotland.

Was previously treated for low stomach acid & leaky gut & took HCL supplements & digestive enzymes for some years but gave up after a while. Am currently taking kefir, kimchi & sauerkraut to help with gut biome. Have poor digestive system & been diagnosed with IBS. Coeliac blood test was negative (I was on gluten at the time) & dr refused to do endoscopy despite the fact my sister is coeliac & I have symptoms per NICE guidelines for further testing.

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Message was to Mary-intussuception. Just checked.



I have made an order to <site deleted>, on the recommendation of others on this site.

It is now fingers crossed, and will see what happens.

I chose this site, as they take credit cards, and at least you have some protection that way.

I will post a genaral message when/if I receive my T3 tablets.



24. Do not post advertisements, links or information of any sort whatsoever, on where or how to obtain UK prescription only medications without prescription. This includes online pharmacies who issue 'prescriptions' on the basis of the completion of a simple health questionnaire.



Sorry, meant to PM Hyburn.


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