Taken too much levothyroxine : Hi. Please can... - Thyroid UK

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Taken too much levothyroxine

Kebabalon profile image
12 Replies

Hi. Please can someone advise me what's best to do? This morning at 5.30am I took my usual 75mg levothyroxine.

This afternoon I was meant to take my vitamins and have accidentally taken another 75mg of levothyroxine. I have drank coffee immediately afterwards and taken my ferrus fumerate hoping it will absorb the amount.

Should I be seeking medical advice or wait and see if there are any effects?

Thanks in advance

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Kebabalon profile image
Kebabalon
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12 Replies
helvella profile image
helvellaAdministratorThyroid UK

Number one - relax!

Many, many members have made similar mistakes. Sometimes they notice an effect from double-dosing. But often not at all.

Of course, care is important and it is a very good idea to be consistent and careful. I don't want to minimise the general importance of proper dosing. But this sort of mistake is really at the lowest possible level of concern.

Bear in mind, when they are testing new formulations of levothyroxine (or similar trials), they give 600 microgram doses of levothyroxine to healthy volunteers. That is eight times your dose. All at once. And these are people who don't even need any thyroid hormone medication.

We do not hear any reports of this causing significant issues.

Unless you really feel an effect, just take your next tablet tomorrow morning, as usual. And enjoy the rest of the day!

Kebabalon profile image
Kebabalon in reply to helvella

Thank you so much for this reassuring information. I can happily continue with my day without worrying. Thanks again

Lilian15 profile image
Lilian15 in reply to helvella

It takes about six weeks for thyroxine to kick in so unless you have taken the whole bottle, there is absolutely nothing to worry about. It might be a good idea to skip your next dose though. When my sister was first diagnosed her GP gave her thyroxine and told her to take ?mcg and if she does not feel any better to increase it to ??mcg and keep increasing until she feels better. He omitted to tell her to put six weeks between increasing. So she took one tablet, didn't feel any better so next time she took 2 tablets, again she didn't feel any better and she kept increasing, but she had no physical effects hers were all mental. She became very paranoic, telling me her husband was trying to poison her, then at a later stage saying she doesn't care. Eventually taking her to the doctor she had gone psychotic (or whatever you would call it). She had to stop taking the thyroxine and she was given some anti depressants. After a few months she recovered completely.

helvella profile image
helvellaAdministratorThyroid UK in reply to Lilian15

It takes about six weeks for levothyroxine dose to stabilise. Not for it to take any effect.

It very much does NOT take six weeks if someone has taken a significant overdose.

Indeed, the critical period is around 48 hours after ingestion. And this is a real problem. A doctor who does NOT understand might think someone is fine after a few hours. But at the 48 hour point, they can deteriorate suddenly - mostly due to that being the highest point of T3 after ingestion. (In most people.)

Lilian15 profile image
Lilian15 in reply to helvella

Thanks Helvella - I stand corrected.

soppysokes profile image
soppysokes

I can only say I recently took 300mg instead of 75mg.accidentally.

I had palpitations for about 1/2 hr or so pretty soon afterward but that stopped and no other problems at all. I am an oldie, have heart issues etc also. If you have no effects from it you will be fine I believe. as always thouggh if feel you need to be reassured call 111 or gp .

Kebabalon profile image
Kebabalon in reply to soppysokes

Thank you very much. I am much happier after these replies.

helvella profile image
helvellaAdministratorThyroid UK

How are you today?

Kebabalon profile image
Kebabalon in reply to helvella

Hi. I have been absolutely fine. No effects at all. Thanks 😊

helvella profile image
helvellaAdministratorThyroid UK in reply to Kebabalon

Delighted to read that. :-)

heafran profile image
heafran

You will probably be fine but maybe ask the pharmacy as they will know your other medications, eg diabetes or heart problems or GP (111) if worried. Hope it helps

Kebabalon profile image
Kebabalon in reply to heafran

Thank you 😊

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