Just a question has anyone become sensitive to thyroid meds all of a sudden, since having b12 injections in jan which i suffered terrible side effects from which slowly passed i have started to have symptoms of being overactive, i have hashimotis and been on meds for 14 years although last aug before my injections i started to take my 75mcg properly as was never told from day dot to take in morning on empty stomach, i would take when id remember and sometimes miss and always take after or before coffee, have never had a problem all these years, is it possible that i now have absorbed more by taking correctly, my thyroid specialist totally stopped my meds for 3 weeks, my tsh jumped to 11 range 0.40 - 4.00 and t4 dropped to 10 from 18.2, my overactive symptons have improved, tremor in legs gone, shaking gone, morning sweats upon waking barley there now, fatigue improved however heart rate still too high, which cardiologist investigating, now back on small dose 25mcg for last 4 weeks, tsh now 9 and t4 12 so specialist advised 50 twice week and other days 25 for another 4 weeks, sorry for long post but curious if anyone else has experienced this?
Has anyone experienced becoming sensitive to th... - Thyroid UK
Has anyone experienced becoming sensitive to thyroid meds after years
I expect you are now absorbing more, but I doubt that 75 mcg is enough to cause the reactions you describe. If you have Hashi's, I think it's far more likely that you've had a Hashi's 'hyper' swing. Do you know how Hashi's works? Because I very much doubt your endo does. 
I was thinking swing but will continue with his advice for now and slowly get levels back whilst waiting for cardiologist results, it may not be thyroid related at all but was feeling so unwell since injections i reluctantly stopped meds and feeling half normal but still not right, its like the b12 upset the apple cart.
Maybe, and maybe not. Could just be a coincidence. Do you have your actual numbers: results and ranges. That would give us a better idea of what's going on.
Dec 2018 75mcg
Tsh 2 and t4 18.2
T4 range 9-20
Tsh 0.40 - 4.00
Was fine on these levels then come jan after b12 all went crazy, hence why i say may not be thyroid related, levels now , other tests since then were tsh 1.75 and t4 17 now after stopping tsh 11.97 t4 10.5
After 4 weeks on 25mcg
Tsh 9.61 and t4 12.7, hope this helps? Cardiologist is testing my cortisol and other heart related bloods as my palps and increased heart rate started after injections and continues off and on.
tsh 1.75 (0.40 - 4.00)
t4 17 (9-20)
And your endo stopped your levo???? I would have said you were under-medicated. You certainly aren't over-medicated with those results. I'm afraid I don't understand.
Yes i know i reluctantly did but ive got to the stage of eliminating as nothing shows in my bloods to explain symptons i was having? Even had pre menopause ruled out, now just need to rule out heart.
So, what are these symptoms you're having?
Around 2 months back since the stopping of thyroid and restarting was having hot flushing during day and upon awakening in morning as soon as i moved, shakiness and nervousness, feeling of spaciness, terrible fatigue that came and went during day, no energy, feeling like hungover without the drinking, bad bloating, normal stools followed by loose, heart palps that continue now that come and go, prickling feeling and tremor type in legs, mainly at rest and waking to numb arm and pins and needles in hand and feet? Still experiencing mild tingling in feet but waking to numb arm or tingling hands has passed, i think ive covered it, racing heart just comes on randomly without exertion ( this is scariest by far) resting heart rate is 90-100
Sounds very much like low B12, to me - have you had that tested? Or, symptoms of under-medication. Trouble is, doctors know nothing much about symptoms. They don't do them in med school.
Yes b12 was tested in dec my b12 stores were low but active was within range this is why i was given 6 loading doses, after injections i suffered extremely heavy legs like concrete, head pressure, tinnitus, gait was off and felt drunk like , pins and needles galore and numbness, took myself to emergency dept twice? Palps also started after injections? All i had prior was some tiredness, then after injections started pretty much every sympton of b12 deficiency, it started after 1st injection but i proceeded with 5 more but just got worse, my serum iron was fine before injections then 4 months after had halved from 16 to 8, ive just had b12 retest on fri along with folate and active, results all within range, i was told it was diet related to why my store levels were low, tested negative to instrinsic factor, very strange
Well, I have no personal experience of B12 injections, but I have heard that they don't suit everyone. Maybe you should pop along to the Pernicious Anemia forum on here:
and have a word with them about it. They know more than I do. But, it really does sound more like B12 than thyroid to me.
Yes im on that forum and im starting to think the same, i can tolerate sublinguals of b12 which are a different form to the injections i had, so my next path to go down after ruling out thyroid or heart problem will be more invasive testing of b12 to make sure im getting enough into cells, i did ask for these with previous gp but was shrugged off and in the end told i possibly have fibromyalgia because of positive ana test, which rhumatologist said thyroid could have caused that reading? also didn't fit many of those symptons and was offered antidepressant which i declined, thanks for your input as makes me now think it is the b12, if so alot of resources have been wasted on numerous scans, ultrasounds, bloods etc plus the last 8 months of my life just existing, thanks again
Yes, well, there's one problem with that: fibro is not an autoimmune disease, and the ANA test is for antibodies. Hashi's is an autoimmune thyroid disease, so it more than likely was the thyroid causing the positive ANA - unless you have another autoimmune disease. Lupus, perhaps? Have they tested for that? Did they actually test for Pernicious Anemia, which is also an autoimmune disease?
Yes lupus was negative and instrinsic factor was negative so i assume that was the PA test, also clear for celiac and hypolari
Taken of Thyroid meds after 18 years 
Is it possible to go overactive on levothyroxine?
Overactive thyroid completely removed 6weeks ago now have some many more problems being underactive does it get any better?
TSH is 6.6, but T4 is 21 ...
Confused with my results, can anyone shed some light
