Missed a dose: Hi I missed a dose on Friday, I... - Thyroid UK

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Missed a dose

Billy2023 profile image
11 Replies

Hi I missed a dose on Friday, I normally leave it by my bed and take it 30 mins before actually getting up but I thought I had taken it but found the pill on floor today. So it's 100mg dose I missed. Will this be a problem? Will I get side effects from this?

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Billy2023
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SlowDragon profile image
SlowDragonAdministrator

Levothyroxine is a storage hormone

Generally take any missed dose as soon as you realise

cut the missed pill in half and take 50mcg alongside your normal 100mcg dose over next couple days

Going forward, get yourself a weekly pill dispenser.

Billy2023 profile image
Billy2023 in reply toSlowDragon

Thank you so much. I am feeling very tired but do you think that is because of other reasons than missed dose? I've just come back from very active holiday, although no alcohol and actually felt great on holiday, with my daughter and find anything too stressful on my body, which is probably fine for normal people, can make me very tired.

SlowDragon profile image
SlowDragonAdministrator in reply toBilly2023

Do you always get same brand levothyroxine at each prescription

What vitamin supplements are you taking

Have you now got results from recent blood test

If you have…….please add results and ranges

For full Thyroid evaluation you need TSH, FT4 and FT3 tested

Very important to test vitamin D, folate, ferritin and B12 at least once year minimum

Also both TPO and TG thyroid antibodies tested at least once

Recommended that all thyroid blood tests early morning, ideally just before 9am and last dose levothyroxine 24 hours before test

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins

List of private testing options and money off codes

thyroiduk.org/getting-a-dia...

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins

bluehorizonbloodtests.co.uk...

Only do private testing early Monday or Tuesday morning.

Link about thyroid blood tests

thyroiduk.org/getting-a-dia...

Link about Hashimoto’s

thyroiduk.org/hypothyroid-b...

Symptoms of hypothyroidism

thyroiduk.org/wp-content/up...

Tips on how to do DIY finger prick test

healthunlocked.com/thyroidu...

Medichecks and BH also offer private blood draw at clinic near you, or private nurse to your own home…..for an extra fee

Amazon07 profile image
Amazon07

Don’t worry, you’ll be totally fine, especially that you are taking Levothyroxin, as that has a 6 week half life in the body. You won’t have any symptoms due to missing this dose. I’m on T3 and I miss doses all the time, not ideal but I’m totally fine!

Fatigue can be a symptom of hypothyroidism so it won’t be due to you missing a dose!

Are you taking Magnesium? I found that it really helps with my energy levels! Just take it at least 3 hours away from any Thyroid medication as it binds T4 and T3.

I take mine before bed and it’s great for a good night’s sleep as well as it’s needed for over 3000 functions in the body!

Best wishes

Anita

tattybogle profile image
tattybogle in reply toAmazon07

Amazon07 , a correction , the half life of Levothyroxine is 7 days .. (not 6 weeks)

the effects of missing a 100mcg dose would be noticed by some people and not by others.

eg if i forget a dose i now notice by about lunchtime that something (quite subtle) is not right ..... eg i notice i'm talking too much, and feeling a bit adrenaline-y... and i may be feeling a bit unusually sleepy by about 5/6 pm

There is often a knock on effect in that the following morning i'm a bit scatty and therefore quite likely to forget to take the following days dose too.

The over all effect of missing 100mcg over the week wouldn't be terrible by any means, but it would be definitely be noticeable to some people.

when a dose of levo is missed it should ideally be replaced as soon as possible.. if i forget a 100mcg dose, i replace it either by taking the full 100mcg as soon as i noticed i'd forgotten it, or by adding 50mcg to the next two days doses. That way the overall dose for the week is not reduced.

Amazon07 profile image
Amazon07 in reply totattybogle

It was an endo (or actually, a few endos) that told me that you had to wait 6 weeks for Levo to take effect as that’s the half life of it.

Has this changed or where did you hear 7 days? Not trying to argue btw just wanting to get the info :-)

Yep, I guess everyone is different and has different experiences, for me it never mattered if I missed a dose (which I didn’t often do) but yeah, others might have a different experience! Thank you for what you said and have a lovely day!

helvella profile image
helvellaAdministrator in reply toAmazon07

Six weeks is how long is widely accepted for the blood levels to stabilise.

Until then, any blood tests could still be changing. (Not that they are ever 100-% stable.)

When you take your first levothyroxine tablet, it can start to have an effect within about 15 minutes. But whether you notice that or not is another matter. It could take days or weeks to feel anything.

Whether you notice or not will depend on many factors such as how severely hypothyroid you are, the dose, and your individual bodily variations.

It has a half-life of around a week.

tattybogle profile image
tattybogle in reply toAmazon07

a quick search of levothyroxine / half life give load of references for this eg:

"This equates to a half-life for T4 of 7.5 days in hypothyroid patients and 6.2 days in euthyroid individuals" ncbi.nlm.nih.gov/pmc/articl...

"The long terminal half-life of orally administered LT4, about 7.5 days, is consistent with once-daily dosing." ncbi.nlm.nih.gov/books/NBK5...

TSH is slow to change , it may take up to 6 weeks for TSH level to adjust and settle following dose change .Hence the wait for 6 weeks before we can take a blood test .. and this is what your endo was referring to , because the TSH result is what they are mostly interested in when monitoring treatment .

Commonly , about 10 days is the time it takes to begin to feel the effect of a small change in dose . but some people may feel it sooner .

But at least 6 week is really needed to get a proper idea of how symptoms will feel once settled on a new dose .. as the body needs enough time to adjust to the changes , and symptoms may continue to change over this time (and longer)

Amazon07 profile image
Amazon07 in reply totattybogle

Thank you so much to both of you 💖

Bearo profile image
Bearo

If you found the pill on the floor does that mean it wasn’t in its strip in the box? I used to leave the strip beside my bed, but then read on here the strip should be kept inside the box, (so I assume that prevents deteriorations caused by light?)

Billy2023 profile image
Billy2023 in reply toBearo

Thank you. I didn't know that!

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