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Latest thyroid tests, trialling T3

Cat_bluenote profile image
Cat_bluenote
โ€ข11 Replies

Hi everyone, any thoughts re- latest results? Feels like the latest one is going in the wrong direction! Started a T3 trial with Roseway , back in July . I have an appointment with them this week.Results 21/6/24

TSH = 2.28 , T4 =19.5 (12 -22) 75%,

T3 = 4.5 (3.1-6.8) 37. 0%

After being on 75 mcg Levothyroxin only since April 24

Results 19/8/24 (same ranges)

TSH = 0.82, T4 = 18.1 (61%), T3 = 4.7 (43.2%)

After adding in initial 5 mcg T3 daily for 6 weeks

Results 18/9/24 (same ranges)

TSH = 2.32, T4 = 13.4 (14%), T3 = 4.4 (35.14%)

After a further 4 weeks of 5 mcg T3 daily

Symptoms now. - Quite tired , muscle ache worse now, but I thought it improved initially. Feeling irritable, brain fog etc. Really wasn't surprised by latest test, I knew I felt worse.

I was having terrible insomnia after starting T3, (but this has improved now.)

So I'd started taking magnesium citrate about an hour or two, before Levothyroxin at bedtime for about a month before I realised I shouldn't! ๐Ÿคฆ

Also the pharmacy changed my brand of Levothyroxin from Accord to Mercury Pharma. I had MP once before but didn't notice any problems. Started those on 24/8/24, I didn't have any choice because they had no other stock and I'd already waited a week.

Would you think the T4 drop has been due to taking magnesium affecting absorption?

Feeling a bit defeated now. Two steps forward, three back! ๐Ÿ˜’

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TiggerMe profile image
TiggerMe

fT4 has dropped due to the addition of T3 which is normal, I feel utterly awful if mine drops below 50% even with T3 at a reasonable level.

Looking like you need an increase in both T3 & 4 but only do one at a time, I'd suggest increasing T4 probably going to need an extra 25mcg as when you started you were only at 75% whilst on 75mcg

Cat_bluenote profile image
Cat_bluenote in reply to TiggerMe

I didn't realise such a small amount of T3 (2.5 mcg twice a day) would do that. It seemed ok after 6 weeks, but then dropped in the last few weeks. But it's all new to me at the moment. Thanks for the advice.

TiggerMe profile image
TiggerMe in reply to Cat_bluenote

It varies between people but for many fT4 can continue to drop for a good few months after adding even a small amount of T3 and it does make you feel awful, it all takes a bit of tweaking to find your optimal doses

Cat_bluenote profile image
Cat_bluenote in reply to TiggerMe

Thanks. I suppose I should be grateful I'm getting the opportunity to try different combinations and aim for optimal. If it was up to my GP I'd still be on 37 mcg Levo! This forum is amazing, and has been a godsend. I'd have had no idea how to help myself. I've found out such a lot. ๐Ÿ˜

RIGBY1978 profile image
RIGBY1978 in reply to TiggerMe

I'm very interested to know why ft4 drops after adding T3. Is it because of further suppression in TSH?

TiggerMe profile image
TiggerMe in reply to RIGBY1978

Now that I can't remember... other than it's a thing ๐Ÿ™ƒ

I shall put a shout out to the ones with better knowledge retention ๐Ÿ˜‰ helvella RedApple radd

radd profile image
radd in reply to TiggerMe

E,

Only just seen this as my notifications aren't working ๐Ÿ™„.

T4 doesnโ€™t always drop with the introduction of T3, but it can for some people and there are numerous causes. You need to revise your deiodinase theory E.

Remember if you are meditating the same amount of T4 when T3 is introduced and the T4 reduces in the blood it is likely being turned into RT3 or other metabolites (such as T4-Sulfate, T4-glucuronide, or Tetrac, etc) by a change in deiodinase behaviours (thyroid enzymes).

This is because as T3 raises in the blood it increases T3 receptor signalling which in turn increases deiodinases D3 to achieve more RT3 (which also helps increase T4 metabolic clearance so reducing T4 further) and D1 to achieve more T3 (so the T3:T4 ratio increases).

Also as FT4 lowers, D2 will up-regulate which increases even more T3 by conversion and lowering T4 further, and widening that gap further.

Thyroid hormones (even medicated ones) are balanced by numerous factors including the transport carriers. When T4 & T3 are competing for binding proteins T3 is the preferred and T4 is more likely to be lost in clearance (eg peeโ€™d out) and FT4 is even easier to pee out as โ€˜freeโ€™ (unbound). Similarly the transporters that pick up FT4 and FT3 to cross the cell membrane much prefer FT3.

Lastly if someoneโ€™s only medicating a small amount of replacement meds due to a partially working thyroid gland, the rising FT3 will reduce TSH so inducing less stimulation of T4 production.

I'm sure there is lots more factors involved but this is off the top of my head.

TiggerMe profile image
TiggerMe in reply to radd

Brilliant as ever Radd ๐Ÿ‘... I just can't store this stuff and regurgitate it in any coherent form ๐Ÿ™ƒ

Cat_bluenote profile image
Cat_bluenote in reply to radd

Thanks, I'll have to read that at least 10 times for it to sink in! Complicated ๐Ÿ˜†

Enuffisenuf profile image
Enuffisenuf

It sounds like you are taking thyroid meds at night? Not sure if it was the magnesium citrate or T3&T4 timing that you realised you had wrong.

I take T4 & T3, but I've been undermedicated with T4 for the last few years as my GP reduced my T4 by 50%.

While this was going on I felt noticeably better taking thyroid meds before bed.

My new GP is upping my T4 back to where it should be and....

recently I started waking up between 04.00 & 05.30 every morning feeling anxious and unable to get back to sleep.

I've switched back to taking T4 in the morning, and T3 split morning & 18.00 ish and I sleep like a baby.

Might it be worth moving your meds to the morning to help with sleep?

Cat_bluenote profile image
Cat_bluenote in reply to Enuffisenuf

I am actually splitting my T4 dose at the moment. 50 at night, and 25 in the morning with the T3. I think I was taking the magnesium citrate too close to the T4 at night. I'll take the magnesium at teatime instead.I used to take T4 in the morning, I don't think it affected my sleep. I've had insomnia for a long time.

Someone recently mentioned that plasma levels of Levothyroxin are lowest 18 hours after consumption, and they said they felt better after they tried splitting their dose, so that there's an overlap. So I thought that I'd try that.

Sounds good that your new GP is helpful. It's hard when your body is adjusting to a new dose, whether it's T3 or T4 , there's usually some new symptom that you're trying to resolve. Takes a lot of patience!

Thanks for replying.

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