On 50mcg Levothyroxine, suffering from insomnia... - Thyroid UK

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On 50mcg Levothyroxine, suffering from insomnia and racing heart!


Hello all.

This is my first post but I've been reading your posts for the last 4 months since being diagnosed with Hashimoto's hypothyroidsim. Have found the forum incredibly helpful and educational.

Over the last 4 months I've been seeing a private Endo once a month in an attempt to find the right dosage of Levo. Have been on 25, 50 & 75mcg of Levothyroxine. Now back to 50mcg (for the past 5 weeks) but have had several weeks of insomnia and racing heart beat/anxiety. Yesterday the Doctor said that my latest blood test results may suggest I am over-medicated and that I should perhaps reduce Levo to 25mcg.

these are the most recent blood results:

TSH - 0.211 mu/L (0.270-4.20)

Free T4 - 20.43 pmol/L (12-22)

Free T3 - 4.8 pmol/L (3.1-6.8)

Ferritin - 89.1 ug/L (13 -150)

Vit D3 - 65.8 nmol/L (75-200 = optimally replete)

B12 - 333 ng/L (191-663)

I'd really appreciate your comments & advice on whether I should drop the dose again, given that the FT3 is only mid-range or whether I should just maintain the 50mcg dose and see if things settle down in another couple of months. The insomnia and panicky feelings are really doing my head in! I've suffered more symptoms from the medication than before I was diagnosed.

thank you.

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20 Replies

Hi AnnieFox, welcome to the forum.

Do you happen to have your results from when you were diagnosed? Just out of curiosity. Did they do any tests to show why you're hypo? Antibodies, or anything?

I don't think you're over-medicated. Your TSH is slightly below range, but that is of absolutely no importance, because your FT4 is well in range, and your FT3 isn't even mid-range. It's FT3 the most important number, and if you lower your dose, your FT3 will go down. You aren't converting terribly well. But, that could be because your vit D3 could be a tad higher - up around 100 would be good - and your B12 is too low. B12 should be at least over 500. Nutritional deficiencies affect conversion. Did you have your folate tested?

But, of course, the most important thing is : how are you feeling? Do you have symptoms? What symptoms do you have - apart from insomnia and anxiety?

Hidden in reply to greygoose

thank you very much for your reply greygoose.

I went to the GP in July because of extreme fatigue, low mood and weight gain. I had been suffering from moderate depression for several years and, of course have been on anti depressants on & off for many years.

These are my initial test results from back in July, before starting on Levo:

TPO Antibodies - 403 ku/L (0.0 - 9.0)

TG Antibodies - 207.8 ku/L (<115)

TSH - 7.87 ml/UL (0.34-5.60)

FT4 - 8.5 pmol/L (7.50-21.10)

Ferritin - 11 ug/L

B12 - 183 (180-914)

Vit D - 49 (25-50 = insufficient)

Haemoglobin estimate 114 g/L (115-165)

I also did a Blue Horizon test about 10 days after starting 25 mcg of Levo and the FT3 result was 4.46 pmol/L (3.1-6.8).

So basically, although I've been on Levo (at various doses) for the past three months, my FT3 level has not changed very much (from 4.46 up to 4.8).

I've never suffered from extended periods of insomnia, nor anxiety, nor fast beating heart before I started taking the medication so I feel these symptoms may be linked to the Thyroxine. Also my appetite is badly affected so it's hard to take in a well balanced diet when you don't feel like eating anything. In a way I wish I'd never been diagnosed and just put up with being fat and tired!

greygoose in reply to Hidden

Yes, I know how you feel, but as you have Hashi's, it just would have got worse and worse.

And having Hashi's explains a lot. A lot of Hashi's people don't convert very well, they need some T3 added to their T4 (levo).

Your antibodies are very high, and that in itself can cause symptoms. You need your TSH suppressed. Doesn't matter how much your doctor kicks and screams, you need your TSH at zero, to calm down the antibodies, and thus the symptoms. Doctors just don't seem to know that. So, your private doctor can reduce your levo if he wishes - as long as he tops you up with some T3.

Why did you do the Blue Horizon test after only 10 days on levo? It takes at least 6 weeks for the levo to take full effect.

It doesn't matter how well balanced your diet is, you will have nutritional deficiencies because you won't be able to digest your food properly. Do you have a lot of upset tummies? It would probably be worth you trying a gluten free diet, to lower antibodies. You could also try taking some selenium - that will also help with conversion. But you do need to supplement the iron, B12 and vit D, to optimise them. Low nutrients cause symptoms, too.

So, until you get all these things sorted out, you won't be able to tell what is causing what. The levo could be totally innocent! lol

Welcome to the forum, AnnieFox.

You aren't overmedicated because FT4 and FT3 are within range. TSH being slightly below range won't make you *feel* anything, it is T4 and T3 levels which make you feel hyper or hypo.

Have thyroid antibodies been tested? It was autoimmune thyroid disease (Hashimoto's) which made my heart race and caused palpitations and insomnia.

Hidden in reply to Clutter

Hi Clutter

thank you for your reply. Yes, antibodies were tested back in July and I've definitely got Hashi (TPO - 403 ku/L range = 0.0 - 9.0 and TgA - 207.8 ku/L <115)

the thing is, I wasn't experiencing any of my current symptoms when I first went to the GP. I went because I was sleeping 10-12 hours a day and still falling asleep during the day and because I'd gained a couple of stone in weight.

Now I'm at the opposite end of the spectrum - can't sleep and can't eat! Somewhere in between would be great! I'm finding it very hard to deal with the insomnia and the palpitations (which make me feel nauseous most of the day so I can't eat).

In your case, did Levothyroxine improve your insomnia and palpitations?

Clutter in reply to Hidden


It could be that a Hashi flare has resulted in a dump of hormone into the blood. You aren't biochemically over medicated but FT4 high in range isn't comfortable for everyone. You could try skipping a couple of days doses and reducing to 25/50mcg alternate days which is equivalent to 37.5mcg daily.

There is no cure for Hashimoto's which causes 90% of hypothyroidism. Treatment is for the low thyroid levels it causes. Many people have found that 100% gluten-free diet is helpful in reducing Hashi flares, symptoms and eventually antibodies.



I had awful palpitations and insomnia but I wasn't treated with Levothyroxine until after I had a thyroidectomy and Hashimoto's died out when there was no longer a target thyroid to attack.

You do sound as though you are hyperthyroid on your present dose. I get migraines, flushes, agitation and palpitations when I am hyperthyroid and my resting pulse is usually 20 above normal with BP a bit erratic. A home BP kit is a good idea. I actually started taking 12.5mcg i.e. 2.5ml oral solution to attain an euthyroid state and my GP said I was "sensitive", but my present endo says it is not uncommon - some endos will say "well for your weight you need to take"...[for me one endo said 150mcg] - no way! The dose increments of 25mcg can be a little coarse and you may need to have more control over the amount you take by using oral solution i.e. 5ml = 25mcg etc. I am on oral solution of LT4 TEVA (more stable, vegetarian and sugar free with glycerol). It is expensive but not on the CCG red list yet, as LT3 is! So if you have absorbency issues then this is the way forward to justify expense of oral solution prescription. I have Hashimotos hypothyroidism and also IBS (although coeliac negative with the cheap NHS IgA test that was only done)... I have had the coeliac symptoms before going gluten free. Have the coeliac test done if you are expressing symptoms and if it comes back negative then refer to Coeliac Society or me for the further tests, as 10% of population come back as false negative ( I am convinced I am one of them but the GP was stoopid and wouldn't do the next tests and I didn't know any better then, so went gluten free anyway - all a learning!) All Hashimotos need to consider this please refer to Chris Kesser for discussion on link between thyroid and gluten - gluten protein molecule is of a similar structure to the TSH receptor sites on the thyroid such that the auto immunity will munch away and they do not regenerate although some GPs declare otherwise! With auto immunity everything in the body will be munched it is non-discriminatory, there is no type of autoimmunity it is simply where the weakness is being expressed - the thyroid unfortunately cannot regenerate like the micro villi in the digestive tract can - so it is not uncommon for us to have other autoimmune "conditions". I find that the oral solution is easier to absorb and quicker so do not have to be careful about calcium and iron intake disrupting absorption. Your Vitamin D3 is low (also check your calcium levels) and your Vitamin B12 needs supplementation get higher in the range above 500 ng/l. I have had 4 years in the world of treacle not being listened to by stoopid GPs, but now found a good endocrinologist Dr Vijay Bangar on the NHS who is allowing me to try LT3 , so now taking LT4 5ml and 3 x 5mcg LT3 and after one week I do not have to do recovery sleep in the day. My thoughts are clearer, I am achieving more. I am sleeping better at night after 10 years on chronic insomnia (I addressed all aspects of sleep hygiene, to include a wool mattress as fire retardants will weaken immune system, also be mindful of other household products in toiletries parabens/SLS and BPA in plastic bottles, as well harsh cleaning products (I use Ecover and vinegar etc.) that will stress the immune system and trigger autoimmunity. I take Vitamin C and Zinc ( also Iron, Omegas 3&6) supplements as I am prone to infection and I let people know that if they have an infection to let me know before I meet them. I do Tai Chi, Yoga and meditation for relaxation. My diet is mostly Paleo, sugar free, gluten free non-goitrogenic and lots of pre/probiotics. I do blends with my nutri-bullet and take neem/tumeric honey balls daily. Still learning about how to make my micro-biome happy. Sorry if there is any duplication of info here... hope it helps :-)

Hidden in reply to amasufindme

thank you amasufindme (great tag name, by the way!). You have given me so much to consider. I will definitely look into getting the oral solution to allow for finer adjustments of dosage and will continue to supplement iron, B12 and Vit D3.


When I was on levothyroxine - my main problem was palpitations, and severe at that. I had to call the ambulance quite often and also my workplace had to once. Saw the cardiologist quite a few times. They were puzzled.

When T3 was added to a reduced levo I immediately felt an improvement but not completely. When I stopped levo and went onto T3 alone I haven't looked back.

Bloods are not my forte and others will respond :)

Hidden in reply to shaws

Thank you Shaws.

I have suggested the addition of T3, but my Endo has ruled that out for all the usual reasons. I think I am going to try taking 25mcg/50mcg Levo on alternate days and see it anything improves.

Glad that you are feeling well on T3. Long may it continue.

shawsAdministrator in reply to Hidden

Endocrinologists have now been warned off about prescribing T3 now regardless of how the patient feels. 25mcg and 50mcg T4 are extremely small doses and sometimes too low a dose can also backfire with the result of more symptoms.

Have you tried taking an antihistamine about an hour before levo, if you then don't have symptoms that day you could ask to change your make of levothyroxine.

A dose of around 100 to 200mcg levo is usual, some take a higher dose. Before blood tests were introduced we were given doses of between 200 and 400mcg of NDT.

Gillybabe48 in reply to shaws

No I disagree 100 to 200 is not normal. On 100 I had racing heart. They give people 200 when they have removed their thyroid.

helvellaAdministrator in reply to Gillybabe48

We are all different.

I have seen doses up to the quite exceptional of about 3000 micrograms.

There are plenty who have not had their thyroids removed who need 200 or more.


No, I haven't taken antihistamines before Levo. I take the Levo as soon as I wake up. Are you suggesting that the antihistamine will reduce the symptoms?

Funnily enough, I asked the chemist for something to help me sleep at night and she gave me a sedating antihistamine. I took one last night and today the palpitations/racing heart beat is better. I didn't make a connection between the two.

I was considering asking for the oral solution of Levo, (made by TEVA) rather than tablet form as you can fine tune your dosage better with the solution.

At one point I was on 75mcg of Levo, but then suffered other symptoms (acute muscle weakness & aches) and my FT4 went up to 24.21 (12-22) so it was decided to bring dose back to 50mcg. I do seem to be very sensitive to the Levo.

How are you getting hold of T3 - paying privately or on NHS?

shawsAdministrator in reply to Hidden

The palps could be due to something in the levo you take. If it resolves by taking antihistamine 1 hour before levo you should ask chemist to switch you to another manufacturer of levo.

Even though your FT4 went up to 24.21 (12-22) they, I assume, didn't test your FT3 which may be low.

Gillybabe48 in reply to shaws

T4 is the one which is crucial and it is high.

Goodlife1 in reply to Hidden

Hi, just wondering how things worked out for you in the end? I'm incredibly sensitive to thyroxine...even a 12.5mcg increase can keep me awake all night yet a lower dose doesn't correct my physical symptoms. Hate the stuff. Interested to hear how you're getting on.

helvellaAdministrator in reply to Goodlife1

The original poster's name now displays as "Hidden". This indicates that they are no longer members of HU. You are unlikely to get a response.

I shall close this thread as there seems little point in leaving it open.

You could try that and see how you feel.

Your t4 is definitely high end of normal.

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