TSH low but T4 low?: my last results confused me... - Thyroid UK

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TSH low but T4 low?

fluffyhat profile image
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my last results confused me as my TSH was 0.04 but my T4 was 13, previously was 18/19. historically my results have done what they are supposed to ie T4 goes up as TSH goes down. but now my TSH is v. low but my T4 is falling, is this anything to be concerned about? My T3 was 1.5 (normal range 0.05 - 2.5).

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fluffyhat
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lynx profile image
lynx

Good q. but remind us all how much t3 and t4 you take a day, as it is a good question.

EG if you were taking t3 x 40 and t4 x 120mcg together daily and you felt awful still with those results. (you know if you take t3 it can reduce tsh) I'm sure you expected your t3 and t4 to rise - where does it go?

fluffyhat profile image
fluffyhat in reply to lynx

i dont take T3, just 75mcgs levo, as i`ve mentioned previously in prev questions I take lithium which is thyrotoxic howver it has made such an improvement to other areas of my life that would not consider coming off it - please dont suggest this as it has literally saved my life. MY gps interpretation of results was worse than mine, she said if the TSH was fine then so everything else would automatically be fine too!!

shaws profile image
shawsAdministrator

What meds are you taking and the doses? If you take T3 alone, your T4 will be very low. TSH should be very low or suppressed. Mine is 0.01 and am fine. GP's shouldn't adjust meds according to the TSH - it can make you worse - unless of course you are overstimulated.

Also did you take your meds after your blood test or before?

fluffyhat profile image
fluffyhat in reply to shaws

I just take 75mcgs T4 but also take lithium, see above.

These bloods were taken first thing in the morning and I had not taken my thyroxine as advised other bloggers

shaws profile image
shawsAdministrator in reply to fluffyhat

I am not medically qualified but I think you could do with an increase maybe 25mcg. It may be that lithium has had an affect on your levo. Dr Toft ex of the BTA says we should have a TSH of 0.2 - 0.5 or even lower if still unwell.

Do you leave 4 hours between levo and lithium. I am not sure if this would do anything re the interactions with but we are advised to take supplements with a gap.

Maybe your GP will increase or add some T3. It may be helpful.

fluffyhat profile image
fluffyhat in reply to shaws

hi there, thnak you for your advice, I always take my lithium at bedtime and my levo first thing because like you i odnt have any evidence to say that you cant take them together but just thought if lithium is thyrotoxic then maybe play on the safe side and separate them.

I know without even asking that my GP would have no truck with T3 - howver my pyschiatrist who I am seeing next week maybe more sympathetic as he originally was going to give me T3 instead of T4.

I have had a return of symptoms but its difficult to know if its environmental instead of physiological in that I have returned to work after being off sick for 7 months but I also changed my workplace and am now working 12 hour shifts in a care home as a nurse, is.it small wonder I am tired and having panic attacks altho I was fine for the first 3 weeks. My GP will say that is why I feel the way I do which to be fair isunderstandable- am tempted to just take an extra 25mgs and see what happens.

shaws profile image
shawsAdministrator in reply to fluffyhat

If people are on optimum medication, they should more or less be able to lead a normal life.

It does sound to me (not medically qualified) that you need an increase especially with panic attacks. Tiredness, of course, could be due to a long shift but when rested it should go.

I would be apt to increase slightly. It is very disappointing to have symptoms return. I hope your phsychiatrist gives you T3.

Duchy82 profile image
Duchy82

The question is how are you feeling? The blood test results should be a guide not gospel, if you feel fine leave it as it is if not ask for a slight increase there is play in those results and i suspect your lithium is probably giving a false low tsh result (i think it has this effect and the gp should know this and adjust your levo accordingly).

I would advise taking your lithium well away from your levo is possible to minimise its interaction.

fluffyhat profile image
fluffyhat in reply to Duchy82

thank for your reply, as you can see from my reply to shaws I do have symptoms but they could be for other reasons.

I was interested to know that lihtium may lower TSH - do you have articles or refs that I could use - tho hopefully pyschiatrist will know this when I see him next week.:)

Duchy82 profile image
Duchy82 in reply to fluffyhat

I had a quick read up on the effects of lithium and it essentially binds with t4 and t3 making it impossible for it to be used by to body or converted for use, i cant find the link again sorry but it is on the internet if you look for it. So from a biological effect would probably be that if you take your levo it goes around your bloodstream for use, effect your pituitary in releasing less tsh, you then take your lithium which binds with your t4 rendering it useless for your body to use.

Its a double edged sword really you need both but they counteract each other.

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