Was on 200mcg levothyroxine (Synthroid) for years and felt amazing, 0 symptoms.
Blood test I have from past on 200mcg; FT4 18 (9-19), and tsh 1.46. Again, felt great, tons of energy.
Went off meds for 16 days Nov 2022, felt like crap, tsh 224 and FT4 6 (9-19), so I went back on 200mcg right away.
After 8 weeks, extreme overmedicated symptoms (insomnia, fast heart rate, extreme brain fog and fatigue), tsh 0.04 and FT4 18 (9-19). Pill taken before test.
Doc lowered all the way to 125mcg and I have slowly been increasing ever since, every 6-8 weeks.
CURRENTLY: on 200mcg for 8 weeks, no pill before test, at 9am
tsh 0.07 (0.32-4)
FT4 17 (9-19) pmol/L
FT3 4.6 (2.6-5.8) pmol/L
Vitamin D - 130 (75-250)
Ferritin 119 (15-275)
B12 365 (138-652)
I still am having brain fog. I have noticed the fatigue has gotten better. Just looking for some advice as I have NEVER been on a higher dosage than this, and this was the dosage previous that I felt great on.
Should I keep waiting on this dosage? I keep seeing that all symptoms should be gone after 6-8 weeks, and my blood tests look quite optimal. Can it take longer for the brain fog to fade?
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Johnfishman22
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Why did you stop your levo for 16 days? It's probably going to take quite a while for you to get back to where you were.
After 8 weeks, extreme overmedicated symptoms (insomnia, fast heart rate, extreme brain fog and fatigue), tsh 0.04 and FT4 18 (9-19). Pill taken before test. Doc lowered all the way to 125mcg
And your idiot doctor's not helping. 25 mcg would have been quite enough to reduce by. Not sure that your symptoms were over-medicated symptoms. They could have been hypo symptoms. There's a lot of cross-over between over and under- medication symptoms.
Taking the pill before the test would only have affected your FT4, not your TSH. TSH doesn't move that fast.
B12 365 (138-652)
But this is probably part of your problem. Low B12 symptoms can be very like hypo symptoms. So, before altering your levo dose, it might be a good idea to raise this level. It should be at least over 550. Have you got a result for folate?
Hey Grey Goose. I stopped because my twin brother did and my doctor said go for it. Was ignorant, and made a big mistake. I think we spoke on my other post.
I went from 0 to 200mcg, which messed me up. My heart rate was crazy high and I couldn't sleep.
Yes, he lowered me way too much and that's why it has been taking so long, 6-8 weeks for every damn dose change.
I will start supplementing B12.
No folate result
Should I continue to wait on this dosage? Can symptoms take longer to resolve than 8 weeks? Going up is going into unknown territory. My results seem fine, not worried about the tsh and doctor isn't, he is focused on getting FT4 around 18 when I felt okay.
EDIT: It has been over a year of tapering slowly, giving my body tons of time to adjust to each dosage.
Don't start supplementing B12 until you've had your folate tested. It should have been done at the same time as your B12.
Symptoms most certainly can take longer than 8 weeks to clear up! Especially when you've really messed up your whole system like that. Could take a hell of a lot longer. Who told you 8 weeks, your doctor? Remember, they have no idea what they're talking about. When I was first diagnosed the endo told me that it would only take two weeks for all my symptoms to disappear! If only.
And, as I said, you need to raise your B12 before changing your dose. That will help enormously, and you might not even need to raise your levo.
I have a doc appointment tommorow, so I will get that. Anything else you recommend bringing up to him? other tests? He is going based off my symptoms since my blood work has been "in range" since 125mcg, which I could hardly function on.
Thank you! Sigh of relief, I guess I am just expecting within 8 weeks everything should be cleared and if it's not then I need to increase dosage, but my blood work is quite good and I have been noticing less fatigue only on week 7.
I hopefully don't have to increase levo. Never have been on a dosage higher than 200mcg, and my tsh would likely be supressed and FT4 maybe over range at 19-20. My FT3 is okay, I seem to be a good converter, what are your thoughts on my thyroid blood labs?
Well, we really don't care about your TSH. It's the least important of the three numbers. And certainly shouldn't be used to dose by!
Most important is the FT3.
FT4 17 (9-19) pmol/L 80.00%
FT3 4.6 (2.6-5.8) pmol/L 62.50%
With an FT4 80% throught the range, and an FT3 62.5% through, you're not such a good converter as all that. The gap between the two is too wide. But, raising B12 might help with that.
In any case, increasing levo is not a good idea because it could make conversion worse, rather than better. And, we now know that high FT4 levels increase cancer risks. So, I really would hold off on raising your levo, if I were you.
Your ferritin could be higher, too. Low ferritin is a main cause of fatigue. Try eating more iron-rich food, like liver once a week, liver paté or black pudding. But, made sure the meal also has a source of vit C, like potatoes or tomatoes, to help absorption.
As with most things hypo, it's a very individual thing. There is no number-fits-all. Ideally, we ought to be able to test more frequantly to see at what point FT4 becomes too high, but the NHS makes sure we can't do that! Unless we're rich.
But, 90% could very well be too high for some people, yes. Think is, if it's so obvious that one is a poor converter, as it is in this case, we ought to be offered T3, not have to fight for it!
Thank you for explaining that. No doubt I’ll forget and ask again. It always bamboozles me as to what FT4 level and FT3 level are considered too high or low even with adjustments to the type of medication/hormone one is on. I’ve decided numbers are a fools game and we must trust our symptoms and always use trial and error/improvement with caution.
I’m not 100% convinced yet aboutconversion issues as some people do just fine with a lower FT3. As we always say, it’s such an individual thing.
Having said that, I would prefer a prolonged release T3 on the market so I would have a choice.
Hey Grey Goose. Just an update and wanted your opinion.
Doc wanted another blood test on 200mcg.
tsh 0.04
FT4 16 (9-19), no FT3
Previous was:
tsh 0.07
FT4 17 (9-19)
Should I even worry about TSH? I do not feel overmedicated AT ALL. I still feel undermedicated. I have been overmedicated and it's very obvious when HR is up and you can't sleep. I sleep too much right now, so easy to fall asleep.
When I felt good my FT4 was 18, so still not there yet.
Going off cold turkey then back on must have messed up my HPA axis or something. Also messed with my dosage requirements cause now it seems like I need a bigger dosage to get FT4 to 18, or just eliminate symptoms.
I am worried my doc may be reluctant to increase dosage because my tsh will be like 0. These results don't make sense to me when I feel like crap undermedicated. How does my FT4 go down but tsh go down too?
No, you certainly shouldn't 'worry' about the TSH, but you should be worrying that there's no FT3 result. It's T3 that causes symptoms, not TSH. And not T4 unless it's really too high.
I don't think that going off levo 'cold turkey' would have messed up your HPT axis, but something could have messed up your conversion - possibly low nutrients? And, we need to see the FT3 to know that.
hi Johnfishman22 I haven’t read all the details above, but I too remember your story. Quick note here to say that (unfortunately) it can be many 6-8 week periods in a row where you titrate changes “low and slow” as your body chemistry settles.
Once I finally got on track, almost all my symptoms resolved EXCEPT extreme fatigue and brain fog. Others come back now and again but it’s those two that are really debilitating to a “normal” life routine!
So… patience as the wisdom of this board helps interpret and guide you on your next moves when it’s time to dose change.
We are all rooting for you! Likely you will get “better” but yes, it takes time.
Thanks for the help! Hopefully this is the dosage. I am adamant about having no symptoms since I had none prior to going off. I felt so good I forgot all about hypo. No brain fog, never tired, very focused etc. So I know that levo works very well for me, never needed T3, never had lingering symptoms. Been over a year of slow titration from 125mcg back onto 200mcg. Wish it worked right away but gotta be patient.
Went off meds for 16 days Nov 2022, felt like crap, tsh 224
CURRENTLY: on 200mcg for 8 weeks, no pill before test, at 9am (which was your last dose before you came off Levothyroxine as above)
It seems like you are wondering if you need another dose increase due to some lingering symptoms, however, I would caution with a TSH that was that high, your body has had quite a time of it. And, it’s common for bodies to take a while to catch up with all the changes.
It’s only been 8 weeks on 200mcg. I would be inclined to give it another 4 weeks, and make a decision from there. As we are getting to our optimum dose, which I would judge by symptoms, it’s wise to give things longer, especially to avoid over medication.
Remember, it’s not all about the numbers but always about how you feel. Right now you feel ‘good enough’ but not perfect. Go with the good enough for a few more weeks longer as 200mcg could still be your best dose.
Was thinking the same thing. Me and my doctor are going by symptoms, and this being the dosage that was good in the past, makes me question why I would need something higher. My FT4 is around where I felt great prior, my tsh is for some reason 0.07. Thank you for the help
Agree with Grey goose and H stardust, stay where you are with 200mcg dose ~ I'd suggest until spring, then re-asses ~ to allow your body's systems a few mths of stability to build on the improvements in symptoms by itself. Working with 'good enough' and allowing your systems to make the best of it and fine tune , can be more effective than repeatedly rocking the boat which is forcing everything to compensate for the continual changes in dose.
Thanks for the insight. If I still don't feel normal after another 2-3 months, what do you think my next move should be? Increase to 225mcg? I am very hesitant to switch medications because synthroid worked magic for me for 8 years. I responded so well, same with my mom and brother. And it would take many more months to maybe another year to fine tune a different medication. Also, based on your own experience with levo and seeing others, can symptoms take a lot longer to go away than 8 weeks while on a dosage?
I agree with the comments on your B12 - it is really much too low. Just for info, the Japanese use a reference range of roughly 500 - 1300 and treat anyone with a result below 500 for deficiency.
Based on the range of your test it was a Total B12 test, usually called "Serum Vitamin B12".
It measures active and inactive B12 in your blood. And of course, nobody knows with this test how much of your result is active and how much is inactive. There is a test available in the UK called Active B12, but whether or not it is available in Canada, I wouldn't know.
The reference range for an Active B12 test result would be something like :
40 - 150 pmol/L or 80 - 200 pmol/L or something in that ballpark. The numbers are lower than they are for serum B12 and the units of measurement are different.
In order for the body to make use of B12 you need folate. It is essential that you don't add folate if your B12 is catastrophically low because it may lead to serious spinal cord damage :
When raising B12 you'll find that there are several different kinds of B12 supplement available. I would always use 1000 mcg methylcobalamin tablets. (I do absorb B12, some people don't if they have Pernicious Anaemia, in which case they would need B12 injections.)
If you can get your B12 a little higher than it currently is you can start adding folate if necessary. For that you would need to add methylfolate 1000mcg tablets rather than folic acid. For more info on folate :
Ideally you would have a level of folate in the upper half of the reference range. If there is no upper level in the range aim for a level which is around 15 - 20 ug/L.
Not the same circumstances as you but I had major surgery in June which completely messed up my system. I was as taking meds throughout but clearly wasn’t absorbing enough, and it took about 5 months to get rid of my hypo/ B12 symptoms. So you will get there eventually. Good luck.
With serum B12 result below 500, (Or active B12 below 70) recommended to be taking a separate B12 supplement and a week later add a separate vitamin B Complex
Then once your serum B12 is over 500 (or Active B12 level has reached 70), you may be able to reduce then stop the B12 and just carry on with the B Complex.
If Vegetarian or vegan likely to need ongoing separate B12 few times a week
Igennus B complex popular option too. Nice small tablets. Most people only find they need one per day. But a few people find it’s not high enough dose
IMPORTANT......If you are taking vitamin B complex, or any supplements containing biotin, remember to stop these 7 days before ALL BLOOD TESTS , as biotin can falsely affect test results
In week before blood test, when you stop vitamin B complex, you might want to consider taking a separate folate supplement (eg Jarrow methyl folate 400mcg) and continue separate B12 until over 500
Post discussing how biotin can affect test results
Will start B12, how much to start with? if I don't see improvement in symptoms in 8 weeks from now, should I increase dosage to 212.5mcg or even 225mcg? Doctor said I can switch to armour thyroid but really don't want too, since levo worked very well in the past for MANY years
I agree with this Johnfishman22 Breathe. It’s a case of one step at a time. I know it’s easier said than done. Trust me. I have lost my father a few days ago and my symptoms are crap but I am pushing through it. It’s not ideal, but the sooner you accept we can’t rush this the better you will feel.
I’m so sorry for your loss. Thank you, I totally agree. I want this to be over with ASAP but rushing will only hurt me, ending up overmedicated and back to the drawing board trying to find my dosage. Hope you sort this out soon for yourself.
The big issue with oral B12 is that you only absorb a small amount - however much you take. The actual amount varies depending on lots of things including our individual make-up.
Many simply take 1000 micrograms daily and hope their level rises over the months. Might not be the best approach but without frequent testing it is very difficult to know what is happening. And there is no evidence that B12 is toxic even in high dose.
Thank you. Do you have any insight to what I should do next? My doc is quite open, told me to wait another 4 weeks on 200mcg synthroid, so 12 total. Can symptoms really take this long to go away or am I just wasting time when I should increase my dosage? This was previously my best dosage, felt amazing, but still feel awful currently, the brain fog is killer. I have updated my profile with any other info you may need as well. Thanks for the help!
Years ago, I used to quite often say something like this:
It can take as long to recover as it did for you to get this bad.
However, I think some found it depressing whereas I meant it to encourage. However much better you have already got, there is still the possibility of further improvement.
In your rather unusual case, I definitely think things might take a long time to get back onto an even keel.
Thank you. Even on this dosage of 200mcg? Would it be best to wait out another month, and if I see no improvement, go up from there? Doc said I can try armour thyroid if it doesn't get better, but I really want to stick with synthroid since I responded well for years, and not sure why I would just no longer respond. I messed with my dosage and my body by going off, so possibly my requirements are larger, but synthroid just randomly not working wouldn't make sense to me.
Hey SlowDragon . Doc wanted another test and you were accurate saying my FT4 would slightly drop. He won't test FT3 anymore, just ft4 and tsh.
Dec 11
tsh 0.07
FT4 17 (9-19)
Dec 28
tsh 0.04
FT4 16 (9-19)
Taking b12 daily. He wants to get my FT4 to 18, where I felt normal. He is not concerned with the tsh and thinks by me stopping suddenly and then going right back on messed with it, and will take time to recover when the dosage is correct. He wants me to go to 212.5mcg.
What are your thoughts? Is is okay for my tsh to be this low? Likely will be suppressed on 212.5 or 225.
PurpleNails Do you have any thoughts? I am in a weird spot, expected this dosage to work since it was amazing in the past for me. How long should I wait before I increase?
Firstly look at nutrients & optimising those then re-assess your FT4 & FT3. It will be a slow process & you have to be patient.
Start supplements & retest in 6 -8 weeks.
Optimising nutrients may resolve symptoms which mimic hypothyroidism & improve thyroid levels / balance or FT4:FT3 back to how you were previously.
Do you have accurate historical results? When you were well on original dose you may not have complete results including FT3 & nutrients so comparing “the numbers” isn’t possible. You are going by the dose you previous took when well, but you are in a different position now.
Went you were well were you more active? Sometimes changes in activity levels, weight & muscle can also alter our replacement needs.
Just got some B12. Doctor only tested b12, ferritin and Vitamin d (130 now, 75-250). The results I have are from march 2021 - I felt so good I forgot to get blood work, I just knew I had to take a pill in the morning and felt great
March 2021 - on 200mcg
tsh 1.46
FT4 - 18 (9-19)
b12 250 ((138-652), its now at 365
no FT3 to compare
I have had results with the exact same FT4 result and felt VERY different
March 2021 - FT4 18, feeling amazing, TSH 1.46
Feb 2023 (after going off, then back on) - FT4 18 - overmedicated symptoms (Fast HR and trouble sleeping key) - TSH 0.04
Dec 11 2023 (NOW) - FT4 17 - (likely 18, no pill before lowered it) - undermedicated symptoms (sleep is fine, HR is fine, extreme fog and fatigue) - TSH 0.07
I am not sure how my blood can be similiar, but I feel so different. It's better to go off symptoms and my doctor is listening. Not sure how that can happen and why my tsh is so low now when it was 1.46 on the same dosage. All of those blood tests are on 200mcg.
I have gone through many weight changes while on 200mcg prior, with no changes in symptoms. Being honest, I have never had hypo symptoms prior to going off synthroid.
I really appreciate your help. Just trying to see what my next move can be to feel normal. I am not a new diagnosis trying to see if synthroid works, I know it works well for me. I just messed up by going off it for 17 days.
shaws Buddy195 do you guys have any input? I updated my profile with all information you may need. Really struggling for over a year now when I was good prior. Any help is very appreciated.
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Any advice please re blood test results
High T3 ERFA Thyroid and Brain Fog
New results 
Blood test results help
Still have symptoms need help with new results
