Does anyone here had problems switching from levothiroxine to synthroid? I started with the same dose and felt terrible heart racing, insomnia, nightmates. Felt better after reducing the dose, but now feel pins and needles all over my body. For information: i had thyroid removed 4 years ago, but they left a small piece of tissue, and Im on 25 mg synthtoid now. Can't believe I need such a small dose with thyroid removed. After surgery started with 125 mg and went through all the agony of overmedicated hyper. Was on levo all these years. Endocrinologist switched me to brand synthroid to correct the dose saying generic variations are plus minus 10% and in my case it's a lot. As soon as I started brand 3 weeks ago I felt like I was going to explode, and reduced the dose from 37.5 dose to 25. Another problem I have is when a dose changes I feel pins and needles all over my body. I guess its due to T3 dropping... Labs TSH 0.27, T4 0.75, T3 is ordered, in the past was normal. Here in US they only want TSH within range, never order T3, you have to plead for it. .
Switching from levo to synthroid dose adjustment. - Thyroid UK
Switching from levo to synthroid dose adjustment.
Remember that Synthroid is just one of the many makes of levothyroxine. Nothing special about it. Subject to the same requirement that it has a potency in the range 95 to 105% up to expiry date.
It isn't a good idea to get a different make every time your prescription is fulfilled. But there is nothing magic about Synthroid.
Some people have found makes other than Synthroid, such as Unithroid, have worked far better for them.
Indeed, Synthroid contains two ingredients which are often suspect of causing problems: acacia and lactose.
If you really have no thyroid, 25 micrograms is simply not going to be enough. I assume they have properly checked that there is no thyroid tissue anywhere?
But many find they cannot tolerate the dose of levothyroxine they need due to other issues, such as being iron-deficient.
I do have a small piece of tissue left after the surgery. Also one parathyroid gland damaged and para hormone level just at lower bottom.
Could that be active? Could it even have grown?
And, to be clear, if your doctor is saying 90 to 110% range for potency, he is the best part of twenty years out of date. It was made more stringent long ago.
I also have a very small piece of thyroid tissue left and according to my Endo no it won’t make enough hormones to do anything for me its too small and no matter how great the surgeon was it impossible to remove every bit of thyroid off the throat. Do I believe this maybe, maybe not !
Batty, After surgery I started on 125 levo and my TSH was 0.07 and endo was cutting the dose until it came to 50 and she couldn't understand why I needed so little. PET showed some remaining tissue. I finally found the dose that worked for me, 37.5. After a year on this dose had symptoms that I thought were hypo- fatigue, muscle and joint pain, but labs showed TSH 0 .27 and endo thought levo didn't work well and decided to try synthroid. Her plan was to see how much I would need and that synthroid is more exact dose. I asked her if we could check what's going on with the tissue and she said I would have to stop thyroxin completely for 6 weeks. What kills me is that when endo tells you to change the dose they don't say what to do if you have heart race and palpitations. My endo says thyroxine is a 7day pill and TSH is a 6 week test. And no advice how to deal with symptoms in between. My physician always says I need to add T3, but endo says no way, it's hard to control the dose, and in Duke where I work and also a patient they don't prescribe T3. It also puzzles me what symptoms are hyper or hypo. Based on labs I'm hyper, and symptoms are more like hypo. I often have pins and needles all over my body and think it's a sign of hypo. Thank you for listening to me, and your comment about acacia makes me think I have to go back to levothyroxine.
Just testing TSH and Ft4 is completely inadequate
Please add ranges on these results
TSH 0.27
T4 0.75
ALWAYS test thyroid as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test
ESSENTIAL to regularly retest vitamin D, folate, ferritin and B12
What vitamin supplements are you currently taking
Pins and needles is frequently low B12 and/or being under medicated for thyroid
If you have no thyroid your Endo or GP should be testing everything except FT3 because for some reason the idiots don’t think its important. I was on Synthyroid 50mcg 2xs a day (thyroid-less) and this pill has an inactive ingredient (acacia) that almost killed me it caused a racing pulse, hives that blistered and lots of issues have since changed back to Levo and majority of my issues have disappeared.
I use walk in labs and select the lab for the test I want done and Quest is sometimes cheaper then Labcorp …. Sad we have to do this!
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