How long before levo takes effect?: Hello - I... - Thyroid UK

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How long before levo takes effect?

Ophelia1 profile image
17 Replies

Hello - I have been taking levothyroxine 100mcg daily for two weeks now. I think there are small (very small) signs of improvement. For example, I feel less tired in the evenings, the constipation seems slightly improved. My longstanding chronic refractory oral thrush seems to be improving, and my joint pain seems to have reduced slightly. I also feel slightly less cold. I wonder whether slow improvement is par for the course or whether this is a sign that levothyroxine might not be working for me.

I would be grateful for any advice and information on this. Thanks in advance :)

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greygoose profile image
greygoose

Nothing happens quickly with hormones - well, not very often, anyway. And, especially not with levo (T4) because it has to be converted into T3. Then the T3 has to get into the cells before you can feel any improvement.

It takes at least six weeks for all that to happen. But, during those six weeks, you might find that although you feel a bit better to begin with, the hypo symptoms can suddenly start creeping back in again. If that happens, it does not mean that levo doesn't 'work' for you, it just means that you're not on the right dose yet, and need an increase in dose.

It's a long, complicated process, and it takes patience - which, I find, most people haven't got. They want instant improvements, which is not how hormones work.

And, we have to increase slowly so as not to shock the body and make things worse. So, increases of not more than 25 mcg every six weeks. When you have your six weekly blood test, always remember to get a print-out of your results. And, when the TSH gets down to about 1 or under, that's when you should be feeling better. If you don't, then you need to either persuade your doctor to test FT4 and FT3 - they don't automatically do that - or get them done privately, so that you can see how well you're converting. Not everyone converts well, and it's low T3 that causes symptoms, not T4 or TSH.

But, I think I've rambled on long enough for one post. We can talk about it more later, if you wish. :)

Ophelia1 profile image
Ophelia1 in reply togreygoose

Hi - Many thanks for your response. I'm not worried about waiting for improvement, but just wondered whether it is normal to have the (slow) response which I am having. It is reassuring to know that it can take some time for levo to take effect :)

greygoose profile image
greygoose in reply toOphelia1

It can take a long time, yes. And, 100 mcg is not a very large dose. Do you have the results from your last blood test that you can post, and let us have a look at?

Ophelia1 profile image
Ophelia1 in reply togreygoose

I last had my bloods tested in October and my bloods were regarded as normal as they fell within the ranges used in the UK. My TSH was 2.50 and my T4 levels were 11.5 . I'm having my bloods tested again by the endo in a month and I will be having my T3 levels tested at that time.

fuchsia-pink profile image
fuchsia-pink in reply toOphelia1

Lab ranges from lab to lab - so it would help if you can add the actual ranges that apply to your test - but it seems likely that you are very low in range ... you will likely feel well when TSH is less than 2 (probably less than 1) and free T4 and free T3 are both in the top third of the range. Just being "in range" (dread phrase) isn't anywhere near good enough!

It's also useful to test key nutrients - us hypos are often low in them - so that means ferritin, folate, vit D and B12. I've had some success with my GP by saying that these are the tests recommended by Thyroid UK

greygoose profile image
greygoose in reply toOphelia1

Your TSH is still much too high. It should come down to 1 or under, but not many doctors understand that. Your FT4 sounds very low, but impossible to tell without the range.

So, you're going to need at least one more increase of 25 mcg levo - don't let them put you off with this garbage of 'being in range'. You know how you feel, they don't.

By the way, it's not a question of 'ranges used in the UK', ranges vary from lab to lab within the UK, so we always need the ranges that came with your results. Labs are only supposed to be a rough guide to your dosage, but how you feel is far more important. Even if your results go slightly over-range, it's not a catastrophe as long as you feel well. :)

SlowDragon profile image
SlowDragonAdministrator in reply toOphelia1

Was this October test done after minimum of 6-8 weeks on 100mcg ?

If yes ......you should have had 25mcg dose increase in levothyroxine immediately

The aim of levothyroxine is to increase dose upwards in 25mcg steps until TSH is under 2

When adequately treated, TSH will often be well under one.

Most important results are ALWAYS Ft3 followed by Ft4.

When adequately treated Ft4 is usually in top third of range and Ft3 at least 60% through range (regardless of how low TSH is)

Extremely important to have optimal vitamin levels too as this helps reduce symptoms and improve how levothyroxine works

Dr Toft, past president of the British Thyroid Association and leading endocrinologist, states in Pulse Magazine,

"The appropriate dose of levothyroxine is that which restores euthyroidism and serum TSH to the lower part of the reference range - 0.2-0.5mU/l.

In this case, free thyroxine is likely to be in the upper part of its reference range or even slightly elevated – 18-22pmol/l.

Most patients will feel well in that circumstance.

But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l.

This 'exogenous subclinical hyperthyroidism' is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l)."

(That’s Ft3 at 58% minimum through range)

You can obtain a copy of the articles from Thyroid UK email print it and highlight question 6 to show your doctor



please email Dionne at

tukadmin@thyroiduk.org

Ophelia1 profile image
Ophelia1

Many thanks for your replies. My vitamin D has been low for some time and my GP prescribed Stexerol which I have been taking for a few months. I've had low ferritin for years and occasional low iron, but have never been actually anaemic. I have had mild low white cell count and have recently been found to have antibodies for lupus, so now have a diagnosis of lupus too. Without going into a rant, I have been telling my GP and other doctors that I thought I had lupus since 2016, but was told - in all seriousness - by the senior partner at my GP surgery that my symptoms and signs were menopause related. I have given up on the NHS and expect nothing from them at this stage :(

in reply toOphelia1

Ophelia,

I was told this morning, by a GP partner, that I was tired because we're in lockdown and I'm not "going out to eat and drink".

I don't know why they're so reluctant to attribute symptoms to thyroid failure.

Josephineinamachine profile image
Josephineinamachine in reply to

Yes, why is that?? I can’t understand this? Is Levo really really expensive or something? If you have a thyroid disorder then WHY do they try and attribute symptoms to other vague (and ridiculous!) possibilities??

Sorry - only just beginning my journey with Hashis and can’t BELIEVE what I’m discovering. The medical response is almost worse than the symptoms.

So stressful. Hope you put that GP in their place!! 😡

in reply toJosephineinamachine

He tried to tell me that anything in range is normal and wouldn't cause symptoms.

He wasn't happy when I asked for clarification: 'so are you saying that if my TSH was 4.99 I wouldn't symptomatic but if it was 5.01 I would be?' 😂 he started ranting about over medication and Atrial fibrillation and osteoporosis, and I "wouldn't be happy when I developed a blood clot, which would cause a stroke and paralyse me on my left side".

The more I think about it, the more I want to make a complaint.

Levothyroxine is cheap as chips. Without getting on my soapbox, this is a feminist issue. This has less to do with cost and more to do with the fact that hypothyroidism is, in the main, a woman's disease. In my opinion.

Josephineinamachine profile image
Josephineinamachine in reply to

Totally agree. I don’t know if you’re at the age of menopause but I’ve been through that. This is very reminiscent of that experience. The whole medical ‘system’ including pharmaceuticals is riddled with patriarchy. Women just don’t matter (even though we now have to contribute to the economy until we’re 68). So frustrating. Mind you, having said all that, I doubt that men fare much better if they are diagnosed with a thyroid disease. I think GPs are told to prioritise gatekeeping resources over treatment now. So is a feminist and political issue. If I had the energy I’d march in protest.

Can you image a hypothyroid march?! It would probably be very slow...

in reply toJosephineinamachine

I agree, men don't fare any better to women in they thyroid world, but I suspect that's because there's not enough research into good thyroid care for the medical world to listen to... Because it's a woman's disease.

I can't get an increase in my life-saving medication which might enable me to work full time, but Viagra is available to men in a heartbeat.

Not that I'd deny it to anyone who needs it, obviously, but the mind boggles over the politics of that! (Sorry, I'm obviously on one tonight! 😂)

I absolutely LOVE the idea of a hypo march! Just to the end of the road and back, and there's plenty of benches to rest on. :D

Josephineinamachine profile image
Josephineinamachine in reply to

Hahaha! Yes, would need to sit down very frequently! 🤣

Oh Viagra. How much money I wonder went into that? And how did it get to over the counter so quickly? And yet women hormones...??

My GP said that now I’m post menopausal I shouldn’t expect to have any energy for anything after the end of a working day (despite my Hashis results right in front of her). What’s worse is she’s a woman (but only in her 30s). 😳

SlowDragon profile image
SlowDragonAdministrator in reply toOphelia1

Hashimoto’s can be misdiagnosed as lupus...or lupus and Hashimoto’s often linked

Absolutely ESSENTIAL to get vitamin D, folate, ferritin and B12 at OPTIMAL levels

Vitamin D at least around 80nmol and around 100nmol maybe better

Ferritin at least half way through range

Folate at least half way through range

B12 at least over 500

What are your most recent vitamin results and ranges

SlowDragon profile image
SlowDragonAdministrator

guidelines on dose levothyroxine by weight

Even if we don’t start on full replacement dose, most people need to increase levothyroxine dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until on, or near full replacement dose

NICE guidelines on full replacement dose

nice.org.uk/guidance/ng145/...

1.3.6

Consider starting levothyroxine at a dosage of 1.6 micrograms per kilogram of body weight per day (rounded to the nearest 25 micrograms) for adults under 65 with primary hypothyroidism and no history of cardiovascular disease.

Also here

cks.nice.org.uk/topics/hypo...

gp-update.co.uk/Latest-Upda...

Traditionally we have tended to start patients on a low dose of levothyroxine and titrate it up over a period of months.

RCT evidence suggests that for the majority of patients this is not necessary and may waste resources.

For patients aged >60y or with ischaemic heart disease, start levothyroxine at 25–50μg daily and titrate up every 3 to 6 weeks as tolerated.

For ALL other patients start at full replacement dose. For most this will equate to 1.6 μg/kg/day (approximately 100μg for a 60kg woman and 125μg for a 75kg man).

If you are starting treatment for subclinical hypothyroidism, this article advises starting at a dose close to the full treatment dose on the basis that it is difficult to assess symptom response unless a therapeutic dose has been trialled.

BMJ also clear on dose required

bmj.com/content/368/bmj.m41

bestpractice.bmj.com/topics...

Kimkat profile image
Kimkat

I wouldn’t say that two weeks is a slow response I would say that is extremely quick, I’ve been on Levo for a year now and I’ve moved up from 25mcg to 75mcg anc I still feel rubbish, I would love to feel improved that quickly 🙂

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