I'd be interested to know if anyone can relate to my Levo experience so far.
In November 2024 I was diagnosed with hypothyroidism following a blood test taken as a result of my experiencing extreme itching in the evenings on a regular basis. It drove me nuts.
Blood tests showed raised TSH, low T4 so I started on 50mg Levothyroxine. I didn't take any notice of the brand as I saw no reason to (in my naivety). Having Googled images for Levo I think I had been taking Almus. A week or two into starting them I experienced extreme fatigue and muscle aches/weakness which quickly resolved and I felt really good - much less tired after work and generally feeling stronger and more energetic (and the itching stopped!).
I did a privately purchased blood test after 2 months and saw my TSH had come down but was still somewhat high, and T4 was optimal.
After 2 months on the original brand, my repeat prescription was a different brand - Teva. Although still 50mg I noticed the tablets were larger but didn't think much of it. However, shortly after starting this brand I experienced a thumping heart. I was experiencing the physical symptoms of anxiety although I was not actually anxious. I ignored it as they came and went until one day my heart was thumping all day and it became actually quite exhausting. I started halving the tablets and the heart palpitations stopped, although I am now feeling less energetic again.
I would be interested to hear any insights that anyone may have to share.
Thank you.
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tge1230
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Is your GP not following up with blood tests? Also if one brand suits you, you can ask your GP tp include that brand name in the first line of the prescription.
Hi Obsidian, yes, I was scheduled for a blood test 3 months after commencing medication but I did my own one privately (a) because I was curious to see what was happening and (b) I wanted testing for antibodies to see if I had Hashi's (which I do) and the NHS test didn't test for that. I have subsequently seen my GP and he has confirmed that if I find out what my initial brand was he will state it on my future prescriptions; interestingly he said most people prefer Teva.
The main point of my post, however, was to see how certain brands have affected other people, and in particular to learn more about the causes of heart palpitations. From what I have seen so far it appears that under medicating can be the cause, although mine stopped when I started taking half a tablet (ie, 25mg) instead.
I raised a yellow card against Tiva Levo because it gave me serious nosebleeds. I won’t touch it. I stick to Mercury or Wockhart. Different brands most certainly are not interchangeable.
So we can offer better advice, can you share blood test results (with ranges in brackets) for:
TSH
FT3
FT4
Plus any antibody and key vitamin tests (ferritin, folate, vitamins D and B12)
If your GP is unable to complete all the above (eg if TSH is within range, some surgeries may not be able to access FT4 and FT3 tests), you could look to do this privately, as many forum members do, for a better picture of your thyroid health:
Regarding heart palpitations, I ended up in A and E with these (plus high anxiety/ tremor/ fast pulse) when my thyroid medication was not optimal. I’ve had similar symptoms when I’ve tried to increase or decrease thyroid medication too quickly. I now adjust super slowly, adding (or reducing by) 12.5mcg (alternate days at first), then daily, until well tolerated.
8.11.24 - Commenced 50mg Levothyroxine (not sure which brand but had gold packet). Initially felt awful then really good.
8.1.24 - Private blood test (Thriva) results (I had only been taking the first brand at this point):
TSH 4.47
FT4 15.7
FT3 3.4 pmol/L (3.1-6.8)
T4 104 nmol/L (59-154)
TPOA 240 klU/L (0-34)
TgAB 92.6 kU/L (0-115)
17.1.25 - GP blood test (been 9 days on 50mg of different brand (Teva) at this point:
TSH 5.73
FT4 14.4
So it seems on the new brand, even at the same dose of 50mg, the numbers were looking less rosy. Also, by this time the heart thumping was becoming an issue. After an A&E visit (as instructed by 111) I reduced the dose to 25mg to try to relieve the palpitations. Had a GP appointment and he condoned my halving the dose, and said if I can determine what the original brand was he will try to ensure I get that one.
Other info, 56 year old female, 5'4", 54kg, run 3 times a week (not mega distance currently due to a pesky achilles injury) and resistance train twice a week. I have a physical job working with horses. My BP is good and Vo2max is 43. I rarely drink alcohol, avoid UPF, don't smoke. Despite this I have high cholesterol but that's another issue! I supplement with Vit D3/K2, turmeric, creatine and collagen, these latter 3 only since the new year.
As TSH should always be under 2 (and many forum members saying they feel best when this is closer to/ under 1) you definitely could do with an increase. As, like me, you have experienced palpitations etc, I would ‘think tortoise not hare’ and add additional Levo super slowly.
Thank you. My next prescription will be 25mg tablets so will afford more flexibility. Is it reasonable to expect the palpitations to subside in due course then? They are alarming as even when running 20 mile cross country races my heart doesn't thump that hard; faster yes, but not thumping out of my chest as on the Levo! It's also confusing as under medicating seems to be a common cause of heart palpitations, but in that case I can't help but wonder why I didn't have heart palpitations when I was on no meds at all, ie pre diagnosis?
I also experienced palpitations when started a small dose of Levo (not before)- Others here have reported similar until thyroid medication is slowly increased.
As a former x country runner, I would definitely cut back on the miles until your adverse symptoms fully pass and your thyroid medication is more optimal. I initially found that trying to continue with my exercise regime made the adverse symptoms worse (ie my pulse was higher) BUT I was able to return to former exercise routine once medication was optimal. I’ve now switched to spinning though- as it’s better for my knees! 🤣
greygoose may be able to offer further advice/ reassurance re cholesterol and hypothyroidism
As SlowDragon advice, try some gentle exercise options. When I was initially diagnosed / whilst adjusting medication I took up pilates and meditation- both of which I have continued with (as I’ve found them beneficial to my physical & mental health)
run 3 times a week (not mega distance currently due to a pesky achilles injury) and resistance train twice a week. I have a physical job working with horses.
You are going to need to reduce training and strong physical activity while you get use to and increase your dose
You need to SLOWLY build up your Ft4 and Ft3 levels
Exercise can rapidly diminish Ft3
Gentle walking or yoga at the moment are more appropriate
Despite this I have high cholesterol but that's another issue!
High cholesterol is side effect of being hypo and will reduce as dose levo increases
If you have an underactive thyroid (hypothyroidism), treatment may be delayed until this problem is treated. This is because having an underactive thyroid can lead to an increased cholesterol level, and treating hypothyroidism may cause your cholesterol level to decrease, without the need for statins. Statins are also more likely to cause muscle damage in people with an underactive thyroid.
High cholesterol is side effect of being hypo and will reduce as dose levo increases
Bizarrely, after my 2 month (private) blood test which showed my TSH reduced by half and T4 up to optimal levels, my total cholesterol went up from 8.0 to 9.4, and the latter was a fasting blood test too! It's a minefield.
I don’t know why you think your T4 was optimal. It was nowhere near optimal and your T3 was dire. All that exercise and hard work on a sick thyroid is a recipe for serious adrenal issues. Do please take notice of what others have said. No running. No gym. Gentle exercise and work will be more than enough. You have a long way to go before you reach optimal so pace yourself.
tge1230 3x marathon runner here, literally countless half’s, 10ks, and for a time I did a “5k a day” in slow training months.
I emphasize advice given to respect your new diagnosis and lean towards taking it easier.
All those runs and such before diagnosis , your thyroid (the body’s engine) was giving up a bit. You just didn’t really know it. Because during that time, your adrenals (your turbo boosters) like cortisol and adrenaline, we’re compensating.
Looks like you caught it early… before a big crash… but extreme incessant itching was the manifestation of a very imbalanced and dysfunctional system. It reflected intolerance or inflammation or low immunity deep down that was manifesting as that itch.
But that wasn’t the only thing your body was experiencing, just the one thing you were aware of. Your low thyroid hormones were depriving hundreds of of cellular processes from the energy and cofactors they needed.
By the time you got diagnosed - you have a hole to dig out of , and taking Levo will do that but now your whole body is in a chain reaction as you adjust to more sufficient levels of thyroid hormones.
There are a million ups and downs in the months and years while things get back to working.
Over time, with hypo, we get very in tune with the ways autoimmune rolls through our bodies.
Thank you, I'm learning a lot here. I am on a skeleton running regime at 3 x per week; normally at this time of year I would be running 5 x per week with much higher mileage and duration, so perhaps the achilles issue is a blessing in disguise! I'm tempted to put myself back up to 50mg Levo again, now that I know from you guys that heart palpitations are part of the process and not just something I will have to put up with forever. I realise we are all unique individuals and that "normal" is something of a myth, but I'd still be interested to know if anyone out there found that they experienced heart palpitations with one brand but not another.
I do recommend you use the search function here, filtering on this thyroid board, using key words like palpitations or the various brands.
Also - as you know none of us here are doctors and no one truly knows anything about you from just a few posts.
But yeah - 50 is the starter dose, 25 will likely just suppress your tsh while not delivering anything close to enough.
There is lots of consensus here that low (increasing by 12.5 a day at most) and slow (waiting at least 6-8 weeks on a consistent dose) is the way to go.
I don’t think anyone here would disagree that back up to 50 is a good choice, and that in 6 weeks you will likely benefit from another increase to 75 (possibly waiting at 62.5 for a week or so first.)
No one of us is the same but manufacturer s guidance does say general dosing is 1.6 mcgs per kilo of body weight.
Both Thriva and NHS state 12-22 as the desirable FT4 range and Thriva said my FT4 was 15.7 which was optimal. FT3 range 3.1-6.8 and mine was 3.4 which was considered normal. Are they incorrect and if so where do you find correct info?
Those ranges, as someone else has written here, don't mean much to an actual patient at all. We all need what we need. And what I need may be much more or much less than you. I might need my FT4 to be 90% of the range to feel well. Or I might need it to be 60% to feel well. It depends how well I convert FT4 into T3 the active hormone. So a doctor will look at a seriously ill patient who can hardly move and declare them well because the numbers are in range or even in the middle of the range. But if that person's sweet spot is 2 points from the top of the range, they are still a long way from well.
Those generic drug leaflets are hopeless, as are the reference ranges. Our bodies tell us what's right and what's not right.
Both Thriva and NHS state 12-22 as the desirable FT4 range and Thriva said my FT4 was 15.7 which was optimal. FT3 range 3.1-6.8 and mine was 3.4 which was considered normal. Are they incorrect and if so where do you find correct info?
If you surveyed the population and determined a range of “normal “ women’s shoe sizes, you would get a range of about 5 to 11 for women.
But if you were a size 10 and the doctor said - well, here’s a size 5.5 for you… no reason it should hurt, normal starts at 5 and you’re now “in range”!
That’s kind of how ranges work.
Normal is defined as the lowest and highest results among about 95% of the population (they lob off the long tails at the very top and very bottom) AND excluding anyone who has a thyroid disorder.
So at the core of the big bait and switch is making a normal distribution (a statistical calculation - not an assessment of symptoms) of euthyroid population numbers and conflate that with the levels us hypo folks “should” have no symptoms at.
Even if we frequently start on only 50mcg, most people need to increase levothyroxine dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until eventually on, or somewhere near full replacement dose (typically 1.6mcg levothyroxine per kilo of your weight per day)
Adults usually start with a dose between 50 micrograms and 100 micrograms taken once a day. This may be increased gradually over a few weeks to between 100 micrograms and 200 micrograms taken once a day.
Some people need a bit less than guidelines, some a bit more
If symptoms of hypothyroidism persist despite normalisation of TSH, the dose of levothyroxine can be titrated further to place the TSH in the lower part of the reference range or even slightly below (i.e., TSH: 0.1–2.0 mU/L), but avoiding TSH < 0.1 mU/L. Use of alternate day dosing of different levothyroxine strengths may be needed to achieve this (e.g., 100 mcg for 4 days; 125 mcg for 3 days weekly).
From what I have seen so far it appears that under medicating can be the cause, although mine stopped when I started taking half a tablet (ie, 25mg) instead.
I’ve had similar symptoms when I’ve tried to increase or decrease thyroid medication too quickly. I now adjust super slowly, adding (or reducing by) 12.5mcg (alternate days at first), then daily, until well tolerated.
Palps are very common when under-replaced and especially when changing a dose.
Happened to me and many of us.
There are of course intolerance to various fillers in different tablet brands.
But also - Levo has a 7 day half life. If you took one pill now . In 7 days you would have 50% of that dose in your blood. So when you take your daily pills it builds on itself over time until in 6-8 weeks you have a stable level of hormone in your blood.
That’s why we wait 6-8 weeks to test, the more weeks the more stable.
And in those 6-8 weeks your whole body (including your heart) is adjusting to having waht will eventually be a full replacement level that s optimal for you.
Only you know yourself, and you def should get the code blood tests that Buddy listed out as a dashboard that you monitor every 8 weeks as you titrate.
But we all caution - that period and especially the first 3-5 weeks can be very up and down. Usually the answer is to hold the line.
Just sharing my experience, and noting yes, it’s very common in the early days of diagnosis and treatment.
If you share more info, we can share our relevant experience, and over time you’ll begin to have a better sense of what’s more usual, and what is cause for concern. Only you will know ultimately. But yes, it’s common when titrating and changing doses even when the dose your on will ultimately settle to where you need to stay.
It can take 1-2 years to get to a full replacement dose. That doesn’t mean it will take 2 years to calm down and feel functional. But hormones take time to ramp up, it’s a long, low & slow journey.
edit- and I see you brand brand new to the forum! Welcome! I actually found this board for the same reason a couple years ago. I thought I was going to have a heart attack with the palpitations I was feeling! As I always say - just because we are hypo doesn’t mean we don’t have other things wrong with us (like heart problems)… so stay vigilant and learn everything you need to to advocate for yourself. But for me and quite a few others, for some it is just what happens and it resolves as we get to full replacement dose.
It's becoming clear that palpitations are a very common part of the early process and that's reassuring. I'm happy to be amongst others who like to have some advocacy over their own health. Thank you very much.
You’ve already received so many useful replies - I just wanted to add that I developed irregular heart beats when my brand of Levo was switched (dose remained the same) . These lasted for months and I eventually had a full cardiology work up, which found no cause for them. The cardiologist was puzzled.
The pharmacy switched me back to my original brand a few months later and the irregular heartbeats stopped immediately.
I’ve heard similar stories elsewhere when brands are switched.
(I was switched from Glaxo Wellcome to Mercury and back.)
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