Hi everyone. For background info, I'm 32 (female). This started in May this year. My gynae did some blood tests including a thyroid test since it runs in the family (I'm not trying to get pregnant).
My results on 5 May were considered within range:
TSH - 3.44 mIU/L (ref range: 0.3500 - 4.9400)
Free T4 - 11.72 pmol/L (ref range: 9.0 - 19.0)
Free T3 - 3.47 pmol/L (ref range: 2.89 - 4.88)
A week later on 12 May, I had a more in-depth general checkup at the GP which also included a thyroid test, this time with different results (didn't test T3):
TSH - 7.16 mIU/L (range: 0.65 - 3.7)
Free T4 - 9.8 pmol/L (range: 8.8 - 14.4)
My GP said she would put me on a trial dose of 25mcg Levo because I had all the symptoms (I was feeling very low energy/depressed, hair falling out, hard to lose weight etc.). She also referred me to an endo but I could only get an appointment in August.
I started my medication of 25mcg Levo on 18 May. I felt great on it and went back for a blood test on 29 June (fasted, took my levo in the morning before my test - didn't know better)
TSH - 1.46 mIU/L (range: 0.65 - 3.7)
Free T4: 12.0 pmol/L (range: 8.8 - 14.4)
This time I saw a different GP who said I can stop my levo since things are in range – but I requested to continue since I didn't want to lose this newfound energy. He agreed and prescribed another round of 25mcg levo to last me till my upcoming endo referral in Aug.
However right around this time, I also started experimenting with extended fasting (20-24 hr fasting) and this wrecked my system a bit, I started bingeing and gaining weight. I stopped this within a month.
On 3 Aug I went to see the endo that was referred to by my GP in May and she asked if I wanted to stop my meds to "wash" them out of my system in order to do some specific testing, I forgot what test it was. I agreed and stopped my levo on 4 Aug cold turkey.
About a month later I experienced a sudden onset of vertigo and dizziness which I'd never experienced before. I went to see a GP and he suspected it was due to coming off my levo cold turkey. He wanted me to get back on it. I did my blood test again, fasted on 1 Sept:
TSH - 2.42 mIU/L (range: 0.65 - 3.7)
Free T4: 10.9 pmol/L (range: 8.8 - 14.4)
I wasn't sure if I wanted to resume my meds at this point even though I'd already gained about 2kg after stopping my meds (without increasing my intake by much, in fact I was exercising more and dieting harder). So I booked a private endo consultation for a week later on 10 Sept with the following more comprehensive blood results:
*note: I'm supplementing with a low dose of iron and a Vit b supplement
Anyway, this endo told me my results are within range but on the 'low' end, so he said he's fine with me taking 25mcg if it makes me feel better.
I've resumed my 25mcg of levo since 11 Sept and I've been having weird reactions all over the place, not at all like the first time I took it when it felt smooth and great. This time round, I felt great at first – clear mind, loads of energy – but by the 4th day I was feeling insomniac, bloated, could feel my heart beating quite hard, excessive sweating etc. I skipped a dose by accident a day ago and I actually felt better, the bloating went down and I could sleep! I've restarted my dose today but my heart is beating hard and fast again.
I'm wondering if I might have been misdiagnosed and might not need levo after all? Is taking the 25mcg (low as it is) affecting my body somehow and making things worse? My next endo appointment is in early Nov, so I'm thinking of just sticking to it for now and monitoring it till then, but any input is appreciated. Thank you for reading this long post!
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It' s important, when you post your blood results, to add the reference ranges, as these vary from lab to lab (although a TSH of more than 2 is always too high). So I'd say you are lucky to have a doc who will give you thyroid meds, albeit at a very low initial dose. You are aiming for free T4 and free T3 to be in the top third of their ref range.
In terms of your recent problems, I suspect you have been given a different brand of levo this time around. They are NOT interchangeable - despite what your GP may tell you - as the fillers are different. A lot of people have problems with Teva (which is one of the few that make a 25 mcg tablet) - although others prefer it as it is one of the few brands which is lactose-free, and some (like me) can take it or leave it.
If you have been given a different brand this time, see if you can get a revised prescription with the previous brand on [or for 50 mcg tablets which you can then halve] or have the GP put "not TEVA" (or whatever) on your prescription - and "yellow card" the brand that didn't work for you.
You should still check you have been given the right brand each time you collect your meds, before you leave the pharmacy.
Have your bloods re-checked after 6 - 8 weeks and see how you are then. Ideally get your thyroid antibodies done next time too. Book an early morning blood test and leave 24 hours from your previous dose of levo. Good luck x
Thanks for your reply! I do think it was the same brand as I'd gotten a prescription from the same GP but I'll check nonetheless, and I'll update my post with the ref ranges as well x
Definitely take the levo and get a re-check as per my previous post. You must feel dreadful with these results
TSH - 3.89 mIU/L (range: 0.27 - 4.20) much too high
Free T4 - 14.3 pmol/L (range: 12.0 - 22.0) 23% through range
Free T3: 3.20 pmol/L (range: 3.10 - 6.80) on the floor - a miserable 2.7% through range
So free T3 is only just in range. It is really really really low. This is the key result: T4 is an inactive hormone which converts to T3, which is needed in every cell in your body (and LOTS is needed in the brain). Your result is absolutely dreadful - not least because free T4 is pretty bad too.
If the jargon is new to you and you don't know much about matters thyroid, please take at helvella's excellent glossary - pinned on the right
I was indeed feeling dreadful the past month after I came off levo, I couldn't explain the weight gain and felt tired and annoyed in general. I'm feeling odd pockets of clarity and energy now and generally just in a better mood.
I'll continue taking the levo as prescribed and go for my blood test as scheduled in early Nov - should be about 8 weeks between now and then.
Thanks for the link and the advice! It's all a bit new and overwhelming to me so I appreciate it! I just have one more question, if you have any insight as to what could have caused my initial TSH readings to fluctuate so much? (re: first reading on 5 May at 3.44, second reading on 12 May at 7.16)
Could be a number of things ... TSH is highest early in the morning and drops during the day, but this prob doesn't explain such a big jump. If you are taking any supplements that contain biotin you must stop them a week before a blood test as biotin distorts the results. And sometimes they just plain make a mistake reading or recording the results.
PS as it's all new ... it's best to take your levo on an empty stomach, just with water, and don't eat or drink anything else for 1 hour afterwards (or 2 hours before). It doesn't matter if you take your levo first thing, last thing or split the dose [although 25 mcg is a bit little to split!]
Also worth a good rootle around the Thyroid UK site to read up on hypothyroidism. Look through the posts and replies here - but bear in mind that 80%+ of hypos do very well on levo once they're on the right dose, whereas the people posting here generally have problems. But it's a lovely friendly forum
Thank you, that's very reassuring. I did feel amazed at the sheer difference in energy after being on this tiny starter dose the first time I took it, so I will monitor things and hopefully find the "right" dosage over time as my body adapts!
Which brand of levothyroxine are you currently taking?
Many people find Levothyroxine brands are not interchangeable.
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.
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
Are you currently taking Teva?
Teva, Aristo and Glenmark are the only lactose free tablets
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
I'm taking Euthyrox, I will look up what brands are available to me (I'm based outside of the UK, but this forum honestly seems much more active & helpful which is why I've posted here).
I've switched to taking levo 3hours after my last meal, right before bedtime. The test of my supplements are taken in the morning or midday!
Even starting on 50mcg, dose still is increased upwards in 25mcg steps until (for vast majority of people) we are on full replacement dose
Levothyroxine doesn’t “top up” sluggish thyroid, it replaces it
As an example....if, when perfectly healthy, your own thyroid made the equivalent of 125mcg levothyroxine....and this metabolism is controlled by pituitary sending messages - TSH (Thyroid stimulating hormone)
Then as your thyroid starts to fail (usually due to autoimmune thyroid disease) ....you might get diagnosed when your thyroid has reduced output to roughly equivalent of 75mcg levothyroxine
Pituitary has noticed there’s a drop in thyroid hormones in the blood....(that’s Ft4 and, most importantly, the active hormone Ft3) ....so to try to make more thyroid hormone ...pituitary sends out stronger message to thyroid - TSH rises up
When GP starts you on 50mcg ....initially you feel a bit better ....as you have 75mcg from your own thyroid and 50mcg levothyroxine
But (here’s the bit many GP’s don’t understand)....levothyroxine doesn’t “top up” your own thyroid output.....well it does very briefly....but the pituitary very soon “sees” the levothyroxine in the blood....and TSH starts to drop
So at the end of week 6 ....TSH has dropped a lot. Your thyroid takes a rest ....has a holiday
So at this point you are now only mainly using the 50mcg levothyroxine....which is actually a dose reduction down from managing on 75mcg from your own thyroid before you started on levothyroxine
So you start to feel worse .....and are ready for next 25mcg dose increase in levothyroxine
Modern thinking ....and New NICE guidelines suggests it might actually be better to start on higher dose
.....but many medics just don’t read guidelines
....and many patients can’t tolerate starting on more than 50mcg and need to increase slowly.
Starting on 50mcg and stepping dose up in 25mcg steps, retesting 6-8 weeks after each increase. But we still very often need to increase up to 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.
Thank you, this is incredibly helpful in my understanding of how Levo works. It also explains why I felt great the first time but "crashed" so much once I stopped taking it even though my blood test results were similar to my initial pre-medicated levels.
I doubt the GP would increase my dose to 50 mcg (as you described, the explanation I've gotten is "you don't need that much since you're still in range and any more will have adverse effects") but I'll ask anyway!
A little update. My GP has agreed to allow me to titrate up to 50mcg and says to pay attention to my symptoms and act accordingly since I convinced her my symptoms are speaking very loudly to me.
In the meantime, just got a blood test back:
TSH - 2.71 (ref 0.65 - 3.7)
T4 - 12.0 (ref 8.8 - 14.4)
This is while I've been on 25mcg levo for about 3.5 weeks. I know the usual procedure is to wait till 6 weeks from my initial dosage but my symptoms are getting worse (extreme bloating and constipation especially) so I'm going to up to 50mcg every alternate day and see how things go (my next endo appointment is in 5 weeks which will give my body enough time to settle in). So, your advice has been quite spot on.
This is likely causing fast heart rate as your body struggling with lack of Ft3
See/contact GP for increase in levothyroxine up to 50mcg
Bloods should be retested 6-8 weeks later
This repeats as dose is slowly increased up until symptoms resolve, typically will need at least 1.6mcg levothyroxine per kilo of your weight. Some people need more
Meanwhile email Dionne at Thyroid UK for list of recommend thyroid specialist endocrinologists.
Likely one you saw was diabetes specialist.
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 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
You need TSH under 2 for a successful pregnancy. I know you are not trying at the moment. Low thyroid hormones (Ft4 and FT3) increases the risk of miscarriage and failure to conceive. Sounds like the second GP didn't know what he was doing. The levo had brought your results just about into an acceptable range - stopping it would of course send them back out of range. You'd normally expect much higher TSH with those low thyroid hormones so you might have a problem with your pituitary gland (central hypothyroidism) - a GP is not equipped to deal with that (nor are most endos). Di d you remember to stop taking the B vitamins a week before the blood test?
Funny you mentioned that! My endo (the one I was referred to by my GP) mentioned in passing that it might be a pituitary gland issue but didn't elaborate. My next appointment with her is in early Nov so I will ask her more about that in detail. I didn't stop the B vits - didn't know better! I will do that for my next blood test.
Slow Dragon is spot on with her advice. I can't see a vitamin D result? Was it tested? It should be pretty high in range for good conversion. All of our hormonal glands including the thyroid, adrenals AND pituitary gland (yours is not very responsive) require good vitamin D levels.
I didn't test Vitamin D - only tested for iron and vitamin B. However, I have been supplementing with 2,000 IU of Vitamin D a day for the past 4 months or so. Vitamin D testing is quite pricey where I am and for that reason the public health GP refused to do it - will look into getting it done privately.
2,000 is good but maintenance dose. It's best to also take Magnesium and Vitamin K2 which are vitamin D cofactors. Magnesium aids conversion of T4 to T3 as well.
Magnesium helps us to regulate cortisol and reduce stress. Being stressed is a massive barrier to conversion; other barriers are anemia and liver and gut issues.
I find some fish oils really hard to digest (bad breath afterwards!) Good quality Cod Liver Oil is ok AND it has vitamin A in it. If it doesn't suit you, you could try a vegan alternative. Don't overdo zinc, as it interferes with copper uptake. However, I take 3 tabs of Neurobalance a day which has zinc, p5p and Magnesium. Not quite enough Mag, but plenty of zinc and the p5p is great for levelling mood and preventing water retention.
I'll look into Neurobalance - I could use some reduction in water retention. It drives me mad as I'm very active at the gym, watch my diet etc. but have such a tough time shifting weight & have to deal with water retention on top of that >
Neurobalance is good but there are other p5p combos. There was an American brand that I used to be able to get hold of (Terry Naturally). Make sure to eat things like nuts and dark chocolate if you're supplementing zinc. Zinc is vital for the thyroid, but zinc also competes with copper and copper is found in abundance in cocoa. Getting the balance right is tricky! (I eat a homemade nut roast alternate weekends.) This link talks about all the benefits of b6 as p5p. It's also really useful during menopause when you can get estrogen dominant symptoms.
You weren't misdiagnosed and yes you're lucky to have a Dr that has recognized your "sub hypothyroidism." I wasn't and ended up with a golf ball sized goiter and lost half my thyroid! That's the risk you take by not taking the medication. If you're tired all the time then yes you need to stay on the medication. It sounds like at this point you're okay with a supplemental dose of 25mcg. However, after your body adjusts to that you may become tired again and need to go up to 50mcg. For example, I started at 50mcg ,since I only have half a thyroid, and then after 6 weeks was still tired so then moved to 75mcg, after 6 weeks moved to 88mcg, where I hit my sweet spot. I would recommend you trying 50 mcg. The dose that you end up on all depends on how your thyroid is still functioning.
I think what's happening to you right now is that when you initially started the medication your body was compensating by rapidly converting T4 to T3 to keep up with your body's need for T3 and you felt some fatigue. Then you introduce the 25mcg and you start to feel better. Then you take it away and start to have symptoms. Then you add it back. Your body is very sensitive to these adjustments and it takes up to 6 weeks for it to adjust. I'm going through the same thing right now.
Thanks for sharing your experience – I'm sorry to hear about what happened to you, but it's certainly eye-opening. I didn't realise how significant this would be.
I'm going to see a GP tomorrow to discuss bumping up to a 50mg dose as I am actually starting to feel the same old symptoms come back (tiredness, low mood, random weight that won't budge, etc - you know!) I've only been on this "restarted" dose of 25mg for 2 weeks now so I'm not sure if they'd be open to it so soon.
I'm actually tempted to just take 50mcg myself even if the GP is stubborn about it...but I know, I know, it's not advisable without medical supervision. ha!
It's certainly not advisable to move up a dose until the 6th week. It's obnoxious but levothyroxine is T4 and T4 is a storage hormone so it takes so long to build up in your system before it really starts doing anything. If you move up too soon you could be overdosing yourself. I'm currently waiting the six-week wait and the symptoms are crummy. Hopefully on your 4th and 6 week your symptoms may improve a little. good luck!
I read an online book called Functional approach to Hypothyroidism by Doctor Kenneth Blanchard who passed away in 2017 but I found the information in his book helpful. I wish I would have known all this information 10 years ago!
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