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Original poster

Levothyroxine side affects

28 replies

decemberchills · 05/12/2023 08:22

Started on 25mg of Levothyroxine 4 weeks ago. For the past 2 weeks my sleep has been really bad. Waking, tossing and turning. My mood has taken a real dip also. I wouldn't say I am anxious but my mind is overdrive.

Has anyone had this after starting in Levothyroxine?

Hoping to get a follow up apt with GP this week but wondering if it is normal for this to happen, while I adjust to it

OP posts:
Spottywombat · 05/12/2023 08:28

It should just make you feel better.

That's a minute dose too.

79andnotout · 05/12/2023 08:35

Sounds like you are anxious. That is a very small dose. Have you got thyroid disease?

I have lots of side effects from thyroid disease but poor sleep isn't one of them, too much sleep is more like it for me.

Gardenlady543 · 05/12/2023 08:39

@decemberchills levothyroxine comes in micrograms, so I expect you're on 25 micrograms. A full replacement dose of levothyroxine is 1.6 micrograms/kg daily) so if you weigh 60kg you'd be on 100 micrograms. What's the reasoning for you being on 25 micrograms?

As already stated it's a very small dose. Levothyroxine is a synthetic version of T4, a hormone in the body that is inactive and will be converted to the active hormone T3. I can't see how it would be causing your current symptoms. It sounds like you have something else going on.

Velvetbee · 05/12/2023 08:44

DS takes 125 micrograms, no side effects other than feeling better.

witchypaws · 05/12/2023 08:51

Gardenlady543 · 05/12/2023 08:39

@decemberchills levothyroxine comes in micrograms, so I expect you're on 25 micrograms. A full replacement dose of levothyroxine is 1.6 micrograms/kg daily) so if you weigh 60kg you'd be on 100 micrograms. What's the reasoning for you being on 25 micrograms?

As already stated it's a very small dose. Levothyroxine is a synthetic version of T4, a hormone in the body that is inactive and will be converted to the active hormone T3. I can't see how it would be causing your current symptoms. It sounds like you have something else going on.

They seem to start everyone on 25, I'm heavy and they did with me. Ended up on 100 which is still under for my weight but they won't increase it any more unless my TSH changes again

Gardenlady543 · 05/12/2023 08:56

@witchypaws this is based on quite old practice. If someone has overt hypothyroidism: "In adults with newly diagnosed hypothyroidism who are under 60 and without ischaemic heart disease it is safe and efficient to start on a full replacement dose of levothyroxine"

doi.org/10.1136/bmj.a801

The guidance is to consider starting levothyroxine at a dosage of 25 to 50 micrograms per day with titration for adults aged 65 and over and adults with a history of cardiovascular disease.

SirVixofVixHall · 05/12/2023 08:56

I found when I first took thyroxine , also 25 mcg, it sent me slightly hyper. I am v sensitive to even tiny dose increases. At the time I stopped taking it , but a year or two later I was much more underactive and needed to start again.
You might not be slightly over, or it might just be your body adjusting. Do you know what your blood test results where before you started it, and have you been tested for antibodies ?

Original poster
decemberchills · 05/12/2023 08:57

Yes sorry @Gardenlady543 I meant micrograms, typo.

OP posts:
Original poster
decemberchills · 05/12/2023 09:13

Thanks for all of the replies.

My TSH was 5.1 so GP said only the lowest dosage required. I am 82KG if that helps.

I previously had hyperactive thyroid following the birth of my 2nd child in 2020. I was on 50 micrograms of neomercozol along with propranolol for 12 months. Later gradually reduced and stopped when bloods showed I was under active region.

Was in remission for over a year until routine bloods in August had me at TSH 4.9. Then Octobers bloods were TSH 5.1

As 5.1 is just over the threshold perhaps I don't need to be medicated? I feel really jittery this morning, similar to how I felt when thyroid was hyperactive in 2020.

OP posts:
79andnotout · 05/12/2023 09:21

They started me straight on 75mg about seven years ago, I was 55kg. I had a history of hyperthyroidism and was on carbimazole for a couple of years in my late twenties, though, so I guess they just went straight in.

SirVixofVixHall · 05/12/2023 10:07

I wonder if your thyroid is still pretty “wobbly”. You sound hyper now. I can feel a dose shift of 12.5 mcg, some people are very sensitive to even tiny changes.
Your levels might not be very consistent. You could try dropping to 12.5, or 12.5 on alternate days but If you don’t have antibodies then your thyroid might actually level out again, you could have had a flare up rather than actual hyperthyroidism.
I would get tested again now, as it has been a month. If you do have antibodies then your TSH should ideally be around 1. I feel underactive if mine goes above 2. At 5 I would be on the sofa, blank and inert, but people vary in how they feel at different levels.

witchypaws · 05/12/2023 10:40

@Gardenlady543 I did the reading but my doctors ignored me and refused to up me from 50 when my TSH was 7 as "it might overdose me"
I changed doctors...

Rodders92 · 05/12/2023 10:46

decemberchills · 05/12/2023 08:22

Started on 25mg of Levothyroxine 4 weeks ago. For the past 2 weeks my sleep has been really bad. Waking, tossing and turning. My mood has taken a real dip also. I wouldn't say I am anxious but my mind is overdrive.

Has anyone had this after starting in Levothyroxine?

Hoping to get a follow up apt with GP this week but wondering if it is normal for this to happen, while I adjust to it

I have been taking thyroxine for years now and was originally started on 50mcg with a much higher starting TSH but when first starting the thyroxine lost a stone in the first 2-3 weeks and felt jittery , my bloods were rechecked and I still had a high TSH so was dropped down to 25mcg and gradually built up to full replacement dose. So I don’t think yours and my response is typical but it can happen. Unfortunately I never lost any more weight afterwards

TreesWelliesKnees · 05/12/2023 10:52

@Gardenlady543 Can I ask where that calculation comes from? I weigh 55kg and am on 125mcg levothyroxine (Hashimoto's). My latest blood test showed a TSH of 3.48. I was considering asking to go up to 150mcg as I'm very tired, but that would be way more than your calculation suggests.

Utini · 05/12/2023 11:02

@TreesWelliesKnees I think that calculation just gives an estimate to use as a starting point. It's fine to then increase / decrease from there depending on blood test results and symptoms so I wouldn't worry about it.

I definitely wouldn't feel well at that TSH, I need to keep mine close to the bottom of the range or even just below, I'd ask if you'd can try an increase and see if symptoms improve.

WinkyTinky · 05/12/2023 11:03

Not to alarm you @decemberchills but I've been on levothyroxine for 7 years and still I often have to have the dosage adjusted. My case is a bit different as I had thyroid cancer and so have to take thyroxine to stay alive! I am fine though, and haven't ever felt any noticeable side effects, not that I can think of anyway.

So I would think the gp will have you in for blood tests every few months to see how the 25mcg is going for you. And if they haven't already advised this, I would ask for regular check ups. It's amazing how minute amounts can make a difference, so it's quite difficult to get it right, and can take years. Just keep on monitoring and changing as you need.

As I say, this is meant to be reassuring, not alarming. I just wanted you not to panic if you're feeling off, you just need to make changes as and when and you will be fine.

WinkyTinky · 05/12/2023 11:05

I meant to say, I'm on 125mcg, but alternate between 125mcg and 100mcg across the week as 112.5mcg seems to be about right for me.

CeciledeVolangesdeNouveau · 05/12/2023 11:07

Er… I’m on 5mg at 50kg. Has someone made a mistake?

Gardenlady543 · 05/12/2023 11:19

@decemberchills they wouldn't normally start someone on meds with that TSH on a one off reading, they would usually just repeat the test in a few months. I was started on a one off blood test as my TSH was 12.5. I was also having fertility treatment and people trying to conceive should have a TSH under 2.5. So you may have been started on a lower dose as your TSH isn't too high, under 5 is the generic goal.

@79andnotout that's the block and replace strategy so different to conditions such as hashimotos.

@TreesWelliesKnees
doi.org/10.1136/bmj.a801
It's advice for a starting dose, it can help guide what kind of dose someone should be on in the long term, but really it has to be adjusted based on bloods. Some people need higher doses than others.

@CeciledeVolangesdeNouveaue that doesn't sound right.

lochmaree · 05/12/2023 11:29

I am on 125mcg. I did find I felt more anxious when I first went onto it but I also have anxiety and on sertraline for that so not sure which! I have another blood test next week for mine as had a recent dose increase after v heavy periods

StrawberriesSW1 · 05/12/2023 11:55

I used it for 3 months in 2020 and started again 3 days ago. Both 25mcg. I'm going to get a higher dose abroad in a few weeks. I lack energy, loosing hair and feel so cold. It was only ever picked up by a fertility doc. I'm at 3.88 at the moment and it should be below 2 closer to 1.5 I was told then.

ImthatBoleyngirl · 05/12/2023 12:05

DD11 has been on Levothyroxine for 3 years now and hasn't experienced any side effects.

ImthatBoleyngirl · 05/12/2023 12:05

I forgot to say she's on 75mg

Lillygolightly · 05/12/2023 12:25

I am on the same dose of 25mg (Hypothyroidism Hashimotos)

Those first few weeks I had lots of heart palpitations and felt a bit jittery, was given a 12 lead ecg and then a 24 hour ecg. I have abnormal T-Waves but apparently not in any capacity that requires action. So that’s all fine.

I’ve been on medication for a few months now, and the jittery feelings and palpitations went away after a few weeks and I have had no other side effects. I’m actually going for repeat bloods tomorrow as I’m trying desperately to get a medication increase and I still feel fatigued and just generally awful, no amount of sleep or rest makes me feel any better. My last levels after being on medication were 3.4 (down from 6.3) so doctors reluctant to change as I’m in range but still feeling terrible. Stupidly I’m hoping for awful results so they will agree to an increase 🙈

One thing I have heard is that different brands of the same drug don’t suit everyone (something to do with the binding agents used in the drug), so it might be worth asking if you could switch to a different brand.

Ponderingwindow · 05/12/2023 12:33

There is some controversy about the correct tsh ranges. Some doctors think the upper tsh range value is too high.

I have never felt any side effects from my thyroid meds unless I was severely over medicated, but at that point my tsh was measuring around 0.01 and I was very hyper. My target tsh value is slightly under 1 because I am a former cancer patient.