Nervousness after levothyroxine: I've just... - Thyroid UK

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Nervousness after levothyroxine

Stubbo46 profile image

I've just started noticing that after 2-3 hours of taking levothyroxine I'm getting the jitters . An extreme feeling of nervousness that lasts about 1-2 hours. I'm on 75 mcg of levothyroxine and just started splitting the 50 and 25 mcg dose . One on night and one in morning. Now I'm getting the jitters twice but not quite as bad. Anyone else getting the same side effects and anyone know what to do about it.

61 Replies
SlowDragon profile image

Looking at your profile you’re male

How long have you been left on 75mcg levothyroxine

This is only one step up from starter dose

Bloods should be retested 6-8 weeks after any dose change or brand change in levothyroxine

Which brand of levothyroxine are you currently taking

Many people find different brands are not interchangeable

As you have Hashimoto’s are you on absolutely strictly gluten free diet?

What vitamin supplements are you currently taking

For full Thyroid evaluation you need TSH, FT4 and FT3 tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12

Ask GP to test vitamin levels

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

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

Is this how you do your tests?

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

List of private testing options

Medichecks Thyroid plus antibodies and vitamins

Thriva Thyroid plus antibodies and vitamins By DIY fingerpick test

Thriva also offer just vitamin testing

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins by DIY fingerprick test

If you can get GP to test vitamins and antibodies then cheapest option for just TSH, FT4 and FT3

£29 (via NHS private service ) and 10% off down to £26.10 if go on thyroid uk for code

NHS easy postal kit vitamin D test £29 via

Elston profile image
Elston in reply to SlowDragon

Hi slow dragon may I ask you a question please? ..If your pottassium comes back low should the doctor give you some or should you eat rich greens with it in such as spinach?

FancyPants54 profile image
FancyPants54 in reply to Elston

Bananas are great for potassium. I haven’t heard of GPs prescribing it.

Elston profile image
Elston in reply to FancyPants54

I eat usually 2 a day but I have to watch my sugar intake as I get candida in my tummy plus I have low blood sugar incidents ? ..My pottassium and vit d drops due to me having adrenal insufficiency? ..

I try to eat lots of sprouts and spinach but I feel ill and im not sure why?..

I have thought maybe these veg bloc absorption of thyroxine?

Jan_Noack profile image
Jan_Noack in reply to Elston

spinach has lots of oxalixc acid..I don't like sprouts so know nothing about them. I did react to the oxalic acid when I tried eating a lot of baby spinach

Elston profile image
Elston in reply to Jan_Noack

What is oxalic ?

SlowDragon profile image
SlowDragonAdministrator in reply to Elston

A banana with breakfast

Not something to supplement, get from food instead

Elston profile image
Elston in reply to SlowDragon

Well I have adrenL insufficiency so my vit d and pottassium drops regularly..Can I ask please? What normal reading should ft3 and ft4 be please?

SlowDragon profile image
SlowDragonAdministrator in reply to Elston

Please write your own new post with latest thyroid and vitamin results

Previous post shows complex issues

Stubbo46 profile image
Stubbo46 in reply to SlowDragon

I've noticed that a lot of people with hypothyroidism are going gluten free. Why is that?

SlowDragon profile image
SlowDragonAdministrator in reply to Stubbo46

Looking at your posts… you have hashimotos and IBS so highly likely absolutely strictly gluten free might help or be essential

ALWAYS get coeliac blood test BEFORE trialing gluten free

About 80% of hashimoto’s patients find gluten free diet beneficial

Stubbo46 profile image
Stubbo46 in reply to SlowDragon

I had a coeliac blood test it was negative. That's when they discovered I had hypothyroidism and diabetes. I assumed that because I didn't have coeliac disease that gluten was ok. Pasta has always made me ill so avoid it but still eat bread , biscuits crackers. Will try cutting it out. Thanks. Tbh big thanks. I've learned more this last few days from you slow dragon and all the other replies I've had than my own GP. 👍

SlowDragon profile image
SlowDragonAdministrator in reply to Stubbo46

Hashimoto's frequently affects the gut and leads to low stomach acid and then low vitamin levels

Low vitamin levels affect Thyroid hormone working

Poor gut function can lead leaky gut (literally holes in gut wall) this can cause food intolerances. Most common by far is gluten. Dairy is second most common.

According to Izabella Wentz the Thyroid Pharmacist approx 5% with Hashimoto's are coeliac, but over 80% find gluten free diet helps, sometimes significantly. Either due to direct gluten intolerance (no test available) or due to leaky gut and gluten causing molecular mimicry (see Amy Myers link)

Changing to a strictly gluten free diet may help reduce symptoms, help gut heal and slowly lower TPO antibodies

As you already had negative coeliac test you can consider going immediately go on strictly gluten free diet

Trying gluten free diet for 3-6 months.

If no noticeable improvement then reintroduce gluten and see if symptoms get worse

Non Coeliac Gluten sensitivity (NCGS) and autoimmune disease

The predominance of Hashimoto thyroiditis represents an interesting finding, since it has been indirectly confirmed by an Italian study, showing that autoimmune thyroid disease is a risk factor for the evolution towards NCGS in a group of patients with minimal duodenal inflammation. On these bases, an autoimmune stigma in NCGS is strongly supported

In summary, whereas it is not yet clear whether a gluten free diet can prevent autoimmune diseases, it is worth mentioning that HT patients with or without CD benefit from a diet low in gluten as far as the progression and the potential disease complications are concerned

Despite the fact that 5-10% of patients have Celiac disease, in my experience and in the experience of many other physicians, at least 80% + of patients with Hashimoto's who go gluten-free notice a reduction in their symptoms almost immediately.

Eliminate Gluten. Even if you don’t have Hashimoto’s. Even if you have “no adverse reactions”. Eliminate gluten. There are no universal rules except this one.

Personally I had zero gut symptoms, 2 negative coeliac blood tests 20 years apart. After 25 years very poor health…..Joining forum 2016 …I saw just how common gluten intolerance was

private endoscopy revealed severe damage as if coeliac. Strictly gluten free diet was astonishing improvement…..

Stubbo46 profile image
Stubbo46 in reply to SlowDragon

Thanks for all the information. It's very very interesting reading. This is the information I got from my doctor. After receiving blood test for everything I got told that I didn't have coeliac but have hypothyroidism and would have to take levothyroxine for rest of life. I asked what has caused it. He said probably an autoimmune disorder but we don't test for it because the treatment is still the same . 3 month on I had to arrange my second blood test. 3 week later I had to ring for my results even though they said they would contact me and they said the doctor would phone me Friday afternoon. When he called he asked what I wanted so I said I'm waiting for blood results. He asked what for. I said thyroid. He asked what dose am I on so I said 50mcg. So he said would put me on 75mcg and asked if that would make me happy. I said I don't know what dose I'm supposed to be on your the doctor. He said he had to go and to see if this new dose improve my symptoms. Didn't even look at results.

SlowDragon profile image
SlowDragonAdministrator in reply to Stubbo46

About par for the course

There are over 2 million people in U.K. on levothyroxine

It’s the 2nd or third most prescribed medication

Doctors training covers thyroid in one afternoon

They rarely seem to read updated guidelines either

Hence almost 120,000 members on here

Learn as much as possible about hypothyroid/Hashimoto’s

Because GP won’t know anything much

You might find this an eye opener

Being male you stand (slightly) more chance of having physical symptoms taken seriously

Predominately autoimmune thyroid disease is a female disease,

Any ongoing symptoms once TSH is within range invariably lumped in with hypochondria, anxiety, depression etc

On levothyroxine most important results are ALWAYS Ft3, followed by Ft4

Ft3 at least 50-60% through range as minimum

When adequately treated many patients will have TSH well below one, or below bottom of range

It’s common to need to push for each dose increase

Or be forced to see endocrinologist if GP won’t increase further

After each dose change or brand change in levothyroxine you will need FULL TSH, Ft4 and ft3 tested. Often necessary to test privately

Test vitamin levels annually and vitamin D twice year when supplementing

Stubbo46 profile image
Stubbo46 in reply to SlowDragon

Got some new symptoms happening now. My toenails are coming off and I'm doing a lot of sweating on a night. Think am going to have to speak to a doctor.

SlowDragon profile image

How much do you weigh in kilo approx

guidelines on dose levothyroxine by weight

Even if we frequently 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 eventually on, or near full replacement dose

NICE guidelines on full replacement dose


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

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

Guidelines are just that ....guidelines.

Some people need more some less

Anxiety is an extremely common hypothyroid symptom

Stubbo46 profile image
Stubbo46 in reply to SlowDragon

I'm 85kg weight

SlowDragon profile image
SlowDragonAdministrator in reply to Stubbo46


85 x 1.6 = 136mcg

Guidelines suggest that you are likely to eventually need 136mcg levothyroxine per day

Dose has to be increased SLOWLY upwards in 25mcg steps. Retesting 6-8 weeks after EACH dose increase

Essential to regularly retest vitamin levels and maintain optimal levels by supplementing

Stubbo46 profile image
Stubbo46 in reply to SlowDragon

Ok thanks . Doctor probably right then.

SlowDragon profile image
SlowDragonAdministrator in reply to Stubbo46

It’s common to feel worse initially as dose is increased

Which brand of levothyroxine are you currently taking

Have you had vitamins tested yet

Are you on strictly gluten free diet

Don't rely too much on those calculations, take them as a guide but not a strict one. I weigh 68kg and am currently on 175 micrograms of levothyroxine (tirosint). I started at 75 micrograms. I luckily have no side effects or symptoms but I was hyperthyroid before my thyroidectomy.

SlowDragon profile image
SlowDragonAdministrator in reply to LiliAmsterdam

But if left under medicated, it’s a good tool to help get dose increased.


I was on 50mcg for 12 weeks and 75mcg for 3 week.

I get a different brand every 4 weeks at the moment and have felt different with every one but doctor and chemist both said they are all the same.

SlowDragon profile image
SlowDragonAdministrator in reply to Stubbo46

Many people find Levothyroxine brands are not interchangeable.

New Government guidelines for GP if you find it difficult/impossible to change brands

Work out which brand is best for you and INSIST on same brand levothyroxine at each prescription

GP could/should write named brand on prescription if necessary

You may need to go around different pharmacies

Many patients do NOT get on well with Teva brand of Levothyroxine. Teva contains mannitol as a filler, which seems to be possible cause of problems. Teva is the only brand that makes 75mcg tablet. So if avoiding Teva for 75mcg dose ask for 25mcg to add to 50mcg or just extra 50mcg tablets to cut in half

But for some people (usually if lactose intolerant, Teva is by far the best option)

Teva, Aristo and Glenmark are the only lactose free tablets

Most easily available (and often most easily tolerated) are Mercury Pharma or Accord

Accord is also boxed as Almus via Boots, and Northstar 50mcg and 100mcg via Lloyds ....but doesn’t make 25mcg tablets

beware 25mcg Northstar is Teva

List of different brands available in U.K.

Teva poll

Once you find a brand that suits you, best to make sure to only get that one at each prescription.

Watch out for brand change when dose is increased or at repeat prescription.

Physicians should: 1) alert patients that preparations may be switched at the pharmacy; 2) encourage patients to ask to remain on the same preparation at every pharmacy refill; and 3) make sure patients understand the need to have their TSH retested and the potential for dosing readjusted every time their LT4 preparation is switched (18).

Levothyroxine is an extremely fussy hormone and should always be taken on an empty stomach and then nothing apart from water for at least an hour after

Many people take Levothyroxine soon after waking, but it may be more convenient and perhaps more effective taken at bedtime

No other medication or supplements at same as Levothyroxine, leave at least 2 hour gap.

Some like iron, calcium, magnesium, HRT, omeprazole or vitamin D should be four hours away

(Time gap doesn't apply to Vitamin D mouth spray)

If you normally take levothyroxine at bedtime/in night ...adjust timings as follows prior to blood test

If testing Monday morning, delay Saturday evening dose levothyroxine until Sunday morning. Delay Sunday evening dose levothyroxine until after blood test on Monday morning. Take Monday evening dose levothyroxine as per normal

REMEMBER.....very important....stop taking any supplements that contain biotin a week before ALL BLOOD TESTS as biotin can falsely affect test results - eg vitamin B complex

Stubbo46 profile image
Stubbo46 in reply to SlowDragon

Thanks slow dragon . I recently got a blood test for thyroid after 12 weeks. I phoned the doctors for results so they made and appointment. The doctor phoned me and asked what I wanted so I said I am waiting for blood results . He then asked what for so I said thyroid so they could change dose accordingly so he said he would put me on 75mcg from 50mcg without any discussion on the results. Then said he had to go. Not very reassuring I can tell you. May have to change doctors. Thanks again slow dragon

SlowDragon profile image
SlowDragonAdministrator in reply to Stubbo46

You will thousands of U.K. patients get thyroid and vitamin testing done privately

A) NHS often only tests TSH

B) extremely important to get test done as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test

C) Especially as you get dose fine tuned, important to test Ft3 and Ft4

D) essential to regularly retest vitamins

Stubbo46 profile image
Stubbo46 in reply to SlowDragon

Ok thanks for all your advice. Will have to sort something out because this is unbearable.

SlowDragon profile image
SlowDragonAdministrator in reply to Stubbo46

Often most difficult dose increase is the one to 75mcg

Levothyroxine doesn’t top up failing thyroid it replaces it. As dose is increased slowly upwards your own thyroid starts shutting down

When hypothyroid we often get high cortisol to compensate for lack of thyroid hormones, it takes several weeks for cortisol to drop after a dose increase

It could be the brand upsetting you. Especially if currently got Teva

Typically you start to feel better after 5-7 weeks on a new dose

Suggest you consider getting FULL thyroid and vitamin testing done at 6-8 weeks on new dose

Extremely important to maintain OPTIMAL vitamin levels

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

Serum B12 at least over 500

Active B12 at least over 70

Folate and ferritin at least half way through range

Extremely common to have low vitamin levels when hypothyroid

Stubbo46 profile image
Stubbo46 in reply to SlowDragon


SlowDragon profile image
SlowDragonAdministrator in reply to Stubbo46

Which brand of levothyroxine are you currently taking

If it’s Teva get new prescription and get different brand

Only test after minimum 6-8 weeks after any dose change or brand change in levothyroxine

Only do test early Monday or Tuesday morning and post back straight away (via priority post box )

Only test as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test

Splitting dose can help tolerate increase.

Also get weekly pill dispenser so it’s easy to see if missed a dose

rick2525 profile image
rick2525 in reply to Stubbo46

I had all the symptoms you have and more!I was diagnosed hypo Aug 20. I was on dosage increments starting 25 mcg ,50mcg,75mcg,100mcg at 6 to 7 week stages. I felt absolute rubbish. No energy fatigue,( stomach cramps due to TEVA which stopped when I changed brand to Accord)

Feeling like a clamp on my head.

My bloods were in normal range at 100mcg but symptoms persisted. I convinced Dr to increase dosage to 125mcg 5 weeks ago and for 1st time in 7 months I feel I am living again. It is a horrendous journey to be on but you will find your way through it by taking note of what SLOW DRAGON and others on here advise because they have been where you are now and so have I.

I found the following helped

Change Brand of tablets

Go Gluten free (I did 6 months ago)

Check vit levels vit D and vit B are optimal.

Do private blood test as nhs wont do ALL the tests you require.

Lots of good advise fromI always Slow Dragon. I always get a print out of my blood results for my own file.

SlowDragon profile image
SlowDragonAdministrator in reply to Stubbo46

You are legally entitled to printed copies of your blood test results and ranges.

The best way to get access to current and historic blood test results is to register for online access to your medical record and blood test results

UK GP practices are supposed to offer everyone online access for blood test results. Ring receptionist and ask if this is available and apply to do so if possible, if it is you may need "enhanced access" to see blood results.

Link re access

In reality many GP surgeries do not have blood test results online yet

Alternatively ring receptionist and request printed copies of results. Allow couple of days and then go and pick up.

Important to see exactly what has been tested and equally important what hasn’t been tested yet

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12


Thyroid hormone replacement needs adequate levels of iron to work effectively.

Members with low iron often experience heart palpations and/or a jittery feeling. Have you had ferritin tested recently?

Not been tested for anything apart from thyroid and it didn't sound like to me that the doctor had even checked the results when upping my dose.

The same thing happen to me I found that taking it at bed time help. And I take Benadryl to help with my nerves .. I found that I sleep well it helped with my nerves until I have blood tested and see the doctor

I’d place money on the brand being the issue - especially if you are swapping brands regularly! Actavis gives me anxiety for a few weeks until it settles and Teva makes me very ill and very hard to sleep. Mercury’s eltroxin is the only only I will get. One of my GPs (various drs at surgery) also said there’s no difference but luckily the pharmacist knew better.

Do you have your results? If you're under medicated you'll have all sorts of symptoms. Your doctor doesn't sound great! I'd call the gp for a copy of your results but for a full picture of how you're going I'd get tested privately by Medichecks or Blu Horizon or any other - get T3, t4 and tsh and if poss b12 folate and D. Then post your results here. By the way most don't feel well til their tsh is 1 or below and their T3 and t4 likely high in ranges.

Through the excellent advice on this forum I changed my brand and it has helped a lot. My old brand had mannitol in it which made me feel awful. Lots of side effects including a sense of anxiousness, extreme nervousness and agitation. I hope this helps and that you get it sorted and feel better soon.

Don't know if this could be the reason, but i had this when i was over medicated, as well as heart palpitations. I would contact your doctors to see if they can do your bloods. The range is quite broad everyone has a different optimum level it took me 3 years of adjustments to find mine and the right dose to go with it. Its so hard trying to find the balance and exhausting.

FancyPants54 profile image
FancyPants54 in reply to

He’s not likely to be over medicated on 75 Levo. He’s only been on that dose 3 weeks so too soon to retest anyway.

in reply to FancyPants54

Okay, was just saying i had nervousness and i was over medicated just sharing what i had..., I did put i don't know if this is the reason. SORRY!

SlowDragon profile image

Teva is the brand that contains mannitol…..upsets or is intolerable for many patients

I yellow carded Tiva. I had the most awful nosebleeds using it. Not that doctors believed it could be the cause. But I know it was. Never had nosebleeds before or since.

I get scared taking my 25mg every morning it scares me my hands get clammy and my lips and I go into a complete panic mood I don’t like it at all wish there was a different way to fix this problem

Try to stop that. It’s not poison. It’s a tiny amount of hormone. And you need it.

Agreed with Fancy pants. You need it and you need more of it.

Hi yes it makes me a little dizzie and shaking but I was told to take all mine first thing on a morning without food? .Were you told by a doctor you could split it ? ...

FancyPants54 profile image
FancyPants54 in reply to Elston

Lots of patients split it. Our GPs are pretty useless with thyroid. Don’t expect them to give you useful advice. You can take it any way that suits you.

Elston profile image
Elston in reply to FancyPants54

Wow ok I never knew that you could split it...Is this because its fast release in your system so that you run out towards teatime?

SlowDragon profile image
SlowDragonAdministrator in reply to Elston

Levothyroxine is slow storage, but many people still find it better to split

In theory it shouldn’t make any difference,in practice many find it does, especially when getting use to increased dose

Stubbo46 profile image
Stubbo46 in reply to Elston

No I decided that myself. Had read a few review about splitting. Might go back to just in morning

Elston profile image
Elston in reply to Stubbo46

Mmm think I would too .Let me know how ya get on?

Dito to what admin are saying. I have suffered the same although on a much higher dose, and was told by both a heart specialist and my endo that some people can be sensative to the medication. It could be the brand and maybe the fillers that you are sensative to. Once you have had all of the tests that Slow Dragon advises be guided by how you feel and work with a good Endocrynologist

I started with same after 15yrs on managed dose . Was on 150mg. Everything was still in normal range inc T3. Are you under a lot of stress? Out of the blue went into a thyroid storm. I'm under a new endo as I'm down to 100mg and storm returns if dose is increased. Not saying it's same but but discuss with your Dr. I've just had a test for cortisol levels with synthicine. I still get get jitters but also getting the underactive symptoms. This one tests T3 and I follow gluten free diet. I've had the precursors for adrenal exhaustion despite taking precautionary measures such as stress management . ( Long story of inept treatment and management of my husband's brain injury and subsequent dementia)

LiliAmsterdam profile image
LiliAmsterdam in reply to Algic

Just a warning hypo and hyper symptoms aren't exclusive. The extreme exhaustion can also be a hyper symptom. Before my thyroid was removed it made me incredibly sick. Apart from the extremely high heart rate, blood pressure, breathlessness, nausea, extreme anxiety, sore muscles and joints, the exhaustion was unbearable. I spent most of my energy that I had on trying to stay awake. It was awful.

As SlowDragon said, the move from 50 to 75 Levo can be a tough one for many of us. Keep going. It’s going to get better.

Slow Dragon’s advice is all excellent. Print it off and make a plan of action from it. Follow the plan.

I got the jitters too at first and I was short tempered. I take 50 mcg once a day in mornings. My Doctor said it would level out and it did, it's been 3 months and I have no problems. I think it was about 2 to 3 weeks before I noticed a difference. I am a 68 year old female. Hang in there....

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