T3 users - difference in potency ?: Hello group... - Thyroid UK

Thyroid UK

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T3 users - difference in potency ?

Caesard profile image

Hello group, I am wondering if somebody noticed differences in potency or response to different formulations, but similar quantities.

I have been using Merck's Novothyral 100 (100T4 and 20T3) and 75 (75T4 and 15T3) for some time now (2 years +) but, due to a plateau in metabolism and symptom relief I have recently switched to Unipharma Greece Dithyron (50T4 and 12.5T3)

Now, the Novothyral is formulated as 5:1 T4:T3 and the Dithyron is 4:1 and therefore, at constant T4 there is 25% increase of T3 for the Greek mix.

However, a single pill of Dithyron which is 50T4 and 12.5T3 has more "feeling" to it than a Novothyral 100 which is 100T4 and 20T3. Actually it feels like the first doses of T3, warmth, energy, mental clarity, and some hyper like agitation.

I am puzzled...why such a difference in effect ? Ok, 25% increase of T3 might be an answer but I've felt it from the first pill, which was half of my usual Novothyral dose. And, a few more days later, the effect is still consistent.

Besides quantity variation, might be the different formulations at work here? Potency? Or the metabolic response to this formulation?

Anybody else noticing this?

6 Replies

I can't comment on the combination treatments you mention, since they're not used in the UK. I think it's likely that there are differences in the formulation of the preparations you've tried.

I take T3 only (no T4 anymore) and I've noticed variations in effect over the years between different brands. The type and number of binders and fillers does vary quite a lot between manufacturers. The way I get around any consequent differences in breakdown and absorption of the pills is to crunch them to a powder in my mouth before swallowing.

Caesard profile image
Caesard in reply to Hillwoman

auch, crunching them is a willpower test of its own for me :)

Thank you for your answer

helvella profile image
helvellaAdministrator in reply to Caesard

Disperse them in water? As the Patient Information Leaflet says you should if not taking full tablets.

Caesard profile image
Caesard in reply to helvella

In complete honesty, I was not aware of this. Will crush them for a change, I can do this. :)

MaisieGray profile image
MaisieGray in reply to helvella

If a tablet needs to be swallowed whole then they should provide lesser doses that can be swallowed whole. If part tablets can be safely/effectively mixed in water, then all those tablets should be mixable in water. It makes no sense to have an absolute rule that isn't applied absolutely, and would seem to imply that mixing part doses in water is less than optimal - or worse.

helvella profile image
helvellaAdministrator in reply to MaisieGray

The documentation does not say that part tablets can be mixed in water. They say that whole tablets can be dispersed in water then taken in that form using a syringe to deliver the precise proportion required.

Many levothyroxine products also say they can be dispersed in water if there is a reason - e.g. children or others who cannot readily swallow tablets.

As I see it, it probably really doesn't much matter whether the tablets are swallowed whole or after dispersion provided they really do disperse/disintegrate in the gut.

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