Hello, I switched to accord from Mercury pharma about 8-12 months ago and have noticed my weight creaping up. I’ve also got dark circles under my eyes all the time and had a lot of hair loss. I’m wondering whether to go back to Mercury pharma. I think is switched due to a supply issue.
If I take my tablets under my tongue, does it still matter what fillers are used and would it still block absorption of some font agree with me?
best, Elide
It's always recommended to have a blood test six weeks after a change of brand of levo to see if it's affected your levels. It rather sounds as if it has because you are displaying hypo symptoms. Highly unlikely the excipients in the tablet would make you put on weight, even if they caused the other symptoms.
All brands of levo are designed to be swallowed, not taken sublingually. They need stomach acid to separate the hormone molecules from the sodium molecules they are attached to.
If you stick it under your tongue, the molecules are too big to pass through the mucus membrane into the blood, so the tablet is eventually dissolved and swallowed. So if the active ingredient, T4, is swallowed, so will the fillers be. I really don't think you can get around it that way. 
Hello,
Thanks for your reply. I’m sure I’ve read if other people dissolving the tablets in their mouth? Is there a report that says it’s not absorbed lingually?
Best, Elide
I'm sure you have read that. The subject is always coming up. But no-one ever says it's a good idea. I expect there are some research papers somewhere about it, but I don't have any. Try doing a search on here for sublingual levo, or something like that.
There are papers which identify impaired absorption in several contexts - such as after bariatic surgery, in those suffering gastroparesis, and other issues. Basically, if the levothyroxine does not go through a sufficiently acidic environment, and then into a basic (alkaline) environment, absorption is impaired.
If simply dissolving the tablets in their mouths was viable, I think someone would have noticed, someone would surely have tried.
As with an awful lot of biology, a tiny bit might get absorbed. But I agree with greygoose and am convinced that most of it is simply swallowed.
I started with this search:
europepmc.org/search?query=...
And then played around a little - adding words like "buccal".
Also, I wrote a blog about transdermal absorption:
Transdermal Levothyroxine
Are you sure you're optimally replaced, because being under replaced can catch up with you.
Do you have a copy of your latest blood results that you can share with us? You are legally entitled to a printed copy of your results, ask at GP reception. In England you can get the NHS app and ask for permission to see your blood results on that by asking at GP’s reception.
When hypo we get low stomach acid which means we cannot absorb vitamins well from our food, regardless of a great diet. For thyroid hormone to work well we need OPTIMAL levels of vitamins.
Have you recently or could you ask your GP to test levels of ferritin, folate, B12 & D3? Private tests are available, see link for companies offering private blood tests & discount codes, some offer a blood draw service at an extra cost. thyroiduk.org/testing/priva...
There is also a new company offering walk in& mail order blood tests in London, Kent, Sussex & Surrey areas. Check to see if there is a blood test company near you. onedaytests.com/products/ul...
Only do private tests on a Monday or Tuesday to avoid postal delays.
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