Just a straight forward question: Can levothyroxine be taken under tongue?
At present I'm prescribed two anticoagulants apixaban and clopidagol, along with lansoprazol to deal with stomach problems caused by the anticoagulants. So far I have not taken any lansoprazol because it affects the absorption of thyroid meds in stomach and this is the last thing I want to happen because I'm really hypo. Past couple of days, stomach/gut really bad so had to take lansoprazol this morning out of desperation. I would be ok taking lansoprazol if there was an alternative way, (such as under tongue) to take levothyroxine.
Thank you for taking the time to read this post.
Whoops just read some previous posts regarding taking levo under tongue and found out its not possible to do this due to molecular structure of levo.
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DizzyD
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How about taking levothyroxine at a different time of day? Maybe at bedtime? That's when I take mine (and always have done).
So-called sublingual is always a questionable approach. I think it is difficult to know how much actually gets swallowed - in my opinion, quite possibly most of it.
You might find something interesting/helpful for this link:
Well, that's where I put mine! They really messed up my whole gut. I'd never been constipated until I took them. But, some people seem to take them without any problems.
Alright then, any thoughts then on what’s happening to me since I take my Levo and Lio sub-lingual…? Always have. It’s certainly working, and seemingly consistently and in the right direction…?!?!
You will see in the above study that the scientists looked at the difference between folks taking levo designed to be taken sublingually and oral levo. The fact that they are comparing the two suggests that you need a different compound of levo to be effective sublingually.
I read that drugs.com article early on and determined that it was unreliable (possibly) because it said the molecules are too large: “Unfortunately, the active ingredients in thyroid medication have molecules that are so large that it is difficult for them to pass through the mucous membranes.”
Then I researched molecule size (but honestly I could not find any reputable source so I am not 100pc sure) but it was enough for me to carry on sub lingual. This was what my googling concluded:
Sublingual > Buccal > Gingival > Palatal having mucosea thickness of 100‐200, 200, 250, 500‐600 micrometer respectively
Vs
Liothyronine and levothyroxine molecules are typically in the range of 0.5 to 1 nanometer (nm), which is significantly smaller than a micrometer.
Further, the new research I just found seems to validate that they are small enough for absorption.
helvella
You say “So-called sublingual is always a questionable approach. I think it is difficult to know how much actually gets swallowed - in my opinion, quite possibly most of it.”
The drugs.com article says similar: “Most of the dissolved/crushed medication ends up swallowed, and moves through the digestive system in the usual way.”
So if that’s the case I guess sub lingual is just highly inefficient, if I’m consistent then that would explain why it’s trending positively for me (even if slower bc I’m losing active medicine in the delivery process).
greygoose - I’ve never heard of the requirement for stomach acid, which would change my approach for sure!
My research finds:
1) 100% conclusive that Levo absorption is very effective in the intestines.
2) There are many studies about the various gut issues that interfere with absorption, but most alternatives suggested still go through the stomach first (ie, in one study with 2 liquid alternatives they said “The liquid solution includes 2 forms both of which entail mixing with a glass of water before swallowing.”)
Found this super helpful - because it too shows the first stop as the stomach:
3) Nothing I’ve found says that there is something in the stomach that is REQUIRED in the process, just that it entails it because it starts in the stomach:
“the absorption of LT4 tablets entails previous gastric disintegration and dissolution, which rely on a normal environmental pH.”
4) And in a footnoted paper, as attached it seems to indicate it’s a good thing to bypass the pH related dissolution and necessity of stomach acidic environment.
Here’s where that comes from the article above:
“Oral Cavity
The sublingual and buccal mucosa are highly vascularized, hence drug degradation by intestinal enzymes can be avoided. Liquid solutions were administered via the sublingual route to correct refractory hypothyroidism (262). The presence of ethanol in the solution favors the permeation of LT4 through mucosal epithelium.”
Footnote: 262. Peirce C, Ippolito S, Lanas A, et al.. Treatment of refractory and severe hypothyroidism with sublingual levothyroxine in liquid formulation. Endocrine. 2018;60(1):193‐196. [PubMed] [Google Scholar]
Link to full footnoted article pdf - See attached pic for text snapshot that seems to support sublingual : researchgate.net/profile/Be...
Other question I would have it confirming the chemical makeup of the tablet vs sublingual liquid were equivalent. Nothing says they aren’t, but nothing says they are either.
Be that as it may, the manufacturers themselves say that the levo pill is designed to be swallowed, not taken sublingually.
Also, if you study blood test results, as I've been doing for years, you regularly find that blood levels are low compared to the size of the dose of levo in those that say they take it sublingually.
Mucosal thickness and size of levothyroxine molecules are not obviously linked. There will be some linkage but not necessarily in a way that allows the numerical values of each to be held up and compared.
It is the sizes of gaps in the mucosa that matter. And the levothyroxine molecule must be considered in the state of hydration - which will be at least pentahydrate but possibly with a "coat" of water molecules increasing its effective size to be considerably greater than a naked levothyroxine molecule.. And also the fact that levothyroxine molecules are zwitterionic which affects its interaction. (And I'm not a physical chemist who is able to judge these things meaningfully.)
Attempting sublingual followed by swallowing does not necessarily mean inefficient - depending on exact meaning of that word in the context!
It is possible that dispersal and even partial dissolving in saliva will actually assist with eventual absorption. At least, as compared against a hard tablet that doesn't actually even disperse effectively.
The pH does appear critical. Every levothyroxine oral solution or gel cap includes excipients to achieve a very tight control on pH in the product.
And the levothyroxine we take is levothyroxine sodium. As I understand, the sodium is removed by the appropriate acidity in the stomach. But this raises questions over what happens if any is absorbed sublingually? And whether the removal of the sodium is significant.
Most discussions about sublingual (and transdermal, etc.) suggest that added substances - e.g. ethanol - change the possibilities, sometimes dramatically.
Unknowns remain: Levo molecule size vs oral cavity gap size; pros/cons dissolution in mouth (saliva and local pH) vs stomach pH and necessity of stomach acid; and formulation changes required for sub-lingual to be effective vs just taking tablet formulated for swallowing. (Role of sodium Na, additions of ethanol etc)
We will leave that to the scientists.
Me, as a study of one: I have seen significant improvements in bloods and symptoms and have always taken Levo and Lio sublingual for the past year.
Im not sure why I started doing it this way, but for some reason I prefer it (now I’m analyzing this and have no idea why) but more so once I realized it was a pattern I figured I should be consistent. So I stuck with it, and leave my mouth alone for an hour (ie, no water, no brushing, no eating/drinking) then at the hour or so mark, I have my coffee & breakfast and get on with my day.
Implications: I am going to plan a switch to swallowing with water as indicated. I will need to time it as if it’s a dosage change as that definitely what will happen.
There is no way to know the comparative availability between what I’m doing vs swallowing, but greygoose says anecdotal experience shows it can be notable.
I am still undermedicated (by the numbers and symptoms) and have just increased Levo on Nov 18 (was 50 Levo, was going slowly towards 75. I am 2 weeks into taking 62.5. Along with steady 10 of Lio/no changes).
I was toying with the idea of finishing out the 12.5 increase for this entire 6 weeks to isolate the impact of a small change. But my impatience also tells me to go up to the full 75 for the rest of the 4 weeks. Without this new sublingual thread I was going to stick with 12.5 on principle to learn, and not sail through a sweet spot.
But, helvella and greygoose any ideas on this new drug delivery change I really should/need to make. The next changes I have in queue for subsequent 6 week timeframes:
- fix my ferritin, and D
- optimize my Levo (I still have 25mcgs more to go based on target dose by weight)
- try to get off T3 and go Levo only (my doctor gave me T3 way too early and I really want to see if I can be Levo only)
Should I… test right now (after 2-3 weeks of a 12.5 Levo increase) and then make the next 6 weeks about the drug delivery change?
Should I finish the 6 weeks isolating the 12.5 Levo increase?
Should I make a few changes all at once - do Vit D, and Ferritin diet?
It’s low. 2 tests this fall showed 7 & 14 range 7-271.
Yuck chicken livers! But it does make sense.
I also think now that results/impact of my 12.5 Levo increase sublingual will not be relevant for future Levo increases swallowed, I’m going to cut this experiment short.
Course of action: 1) test even though only 3-4 weeks into a 12.5 increase, because why not, 2) start the 6 week clock again and 3) start swallowing the meds AND change diet for Ferratin increase.
This is a summary of what I have read up and found out about iron supplements over the past few years. I am not in any way medically trained. You are strongly encouraged to check every detail before making any decisions for yourself.
I was toying with the idea of finishing out the 12.5 increase for this entire 6 weeks to isolate the impact of a small change. But my impatience also tells me to go up to the full 75 for the rest of the 4 weeks.
Personally I wouldn't do that. It is best to leave a full six weeks on the same dose. Never a good idea to change horses mid-stream. Experience has told us that it takes at least six weeks for everything to settle down.
- optimize my Levo (I still have 25mcgs more to go based on target dose by weight)
That is only a rough guide, not to be taken seriously as an optimal dose. This idea first started as a way of calculating how much levo to give someone who's just had a TT, and to be titrated from there according to the patient's needs. Quite how it got to be an absolute for all hypos I really don't know, but it should not be taken as such.
- try to get off T3 and go Levo only (my doctor gave me T3 way too early and I really want to see if I can be Levo only)
Why did your doctor give you T3, then? He can't have thought it was 'too early'. Personally, I wouldn't rock the boat. What is going to happen if you find you cannot be on levo only? Will you get your prescription back? Will you ever be able to get back to they place you are now? It's a pretty serious thing to do.
1) test even though only 3-4 weeks into a 12.5 increase, because why not,
Because it's pointless. The results will be unreliable.
3) start swallowing the meds AND change diet for Ferratin increase.
You should only change one thing at a time, because if you don't, you will have no idea what is helping and what is making things worse.
See, this is why we need our objective forum-mates. To talk me off the ledge of impatience lol! I am laughing at my sneaky subconscience trying to justify changing more than one thing, faster than 6 weeks, and thinking it’s a good idea!!! Patience is so hard!
Ok ok ok, I’m back on track.
I’m going to finish my 6 weeks with the 12.5 increase full stop. No more decisions until my 6 weeks is up. I have my list of next steps I will choose from then.
Ps re my Lio/T3
I am in the US. My doctor is really smart and very well intentioned, he’s a doctor who treats others in my family and has for about 20 years (which is rare even in the US to have that kind of personal family relationship). Therefore, I am lucky in that I am able to match my blood test and med prescriptions needs to my symptoms and requests. No risk of not being able to get it again.
So why am I on Lio in the first place? My wonderful well intentioned doctor (GP/family doctor) - as I learned quickly - knows NOTHING about thyroid. Put me on 50 Levo when first diagnosed in Aug22 and when I was still symptomatic after 9 months - instead of increasing Levo, he had the bright idea to drop Levo to 25 and add 10 Lio. I remember when he did it, he had said that he looked into this “experimental” approach, and I had googled it too, so I was like - cool! But now in retrospect , we should have simply gone from 50 starter dose to 75. But alas, we jumped into T3 combo. This happened right before I stumbled across this board - when he had no answers for all my many many questions and I started trying to understand it myself.
Further evidence to his well intentioned lack of knowledge was that he didn’t ask for the right blood tests either and didn’t even know T3 uptake was useless and when I questioned it he just didn’t answer. But once this board set me straight, I gave him a list of tests and he wrote the new prescription.
So for the past 6 months I have course corrected with this boards genius advice, and every six weeks I email my doctor and ask him for a blood test Rx and a new/refill for whatever Levo and Lio I need at that time.
So I think I should slowly at some point in the future drop the T3 and see if Levo is enough for me. Because it is a big pain to count and chop all these pills every day, would love one Levo once day!!
Well, good luck with that! If I was lucky enough to get T3 without a hassle, I'd cling on to it for dear life! I wouldn't take the risk of coming off it just to see if I can do without it. It just doesn't seem worth it, to me.
But, do you have any lab results from the time you were on only 50 mcg levo?
Short answer is I didn’t get the right full bloods, nor fully consistent things tested over time, until I was on the Lio (having found this forum at that point). So frustrating but it’s all I got:
Have Aug18 4 years before diagnosis for comparison
TSH 2.9 ( .4- 4)
FT4 1.1 (.9 - 1.8)
Total T4 7.8 (4.5 - 12.5)
Total T3 111 (70 - 205)
Aug22-at diagnosis - pre any meds
TSH 85 (.45-5.33)
FT4 .34 (.49-1.48)
Total T4 3.6 (6.09-12.23)
Total T3 74 (87-178)
Sept22-started 50mcg Levo
Nov23
TSH 2.049 (.55 - 4.78)
FT4 1.22 (.89-1.76)
Nov23 Symptom check
Most symptoms cleared up except debilitating fatigue
Jun23
TSH 1.41 (.45-5.33)
Total T4 8.81 (4.5-12)
Total T3 105 (87-178)
T7 3.4 (1.22-4.86)
In July I started the Lio (ie dropped to 25 Levo and added 10 Lio)
Any thoughts on scanning those? Any insights that pop out?
As you say, the correct tests were not done. To get an idea of how well you convert, you need FT4 and FT3 tested at the same time when on T4 only, so that you can compare them. So, these results tell you very little except that you were hypo.
Do you have Hashi's? Hashi's people are very often poor converters.
I have to take Omeprazole which is a PPI like lansoprazol, take it at night and Levothyroxine in the morning as I was advised by my GP to take it at least 4 hours apart due to potential absorption issues of the Levo. This is written on the prescription. Sometimes I have taken the Omeprazole early evening if having gastric symptoms.
If you have gastric issues why not give it a go but leave the required gap between the Omeprazole and Levo, have you been advised on a gap between to anti coagulants and the lansoprazol?
I can see your dilemma but It may be an idea to discuss this with a pharmacist or GP for advice as it is not pleasant suffering from either gastric or Hypo symptoms and doubt that the Levo can be absorbed without the gut which is where it will probably end up..
I wouldn’t bin your lansoprazole as in an earlier reply as they have been prescribed to either protect the gut from the effects of the coagulants which can be problematic and your gastric symptoms.
It’s also worth mentioning that if you take a PPI (i.e. lansaprazole or omeprazole) then this may affect your B12 levels so worth monitoring them more regularly. B12 from food requires acid to cleave and break down the molecules in the protein, it also requires intrinsic factor to be secreted by the parietal cells in the stomach for B12 to then use it as a co-factor for absorption in the intestines. PPI’s inhibit the secretions of parietal cells and so reduce available stomach acid and intrinsic factor.
If you have B12 injections is should bypass much of this process so can be a good way to keep levels up if you are affected.
Hi DizzyD. I have had horrible trouble with all thyroid medications for the last 10 years. I tried them all. I had constant bad acid reflux since I started taking Levothyroxine. All doctors denied that it was a cause for my reflux. Just in September I read that I can take Armour (Thyroid ND) sublingually and I tried and magic ...most of the reflux is gone. I just had my blood tests and my TSH is at 5 and T4 is in normal range, so just a little bit too high on the TSH but its working. I stopped taking all thyroid medicine over the summer and that was really bad. My TSH shot up to 23 and now it's a 5 with the sublingual method so it's absorbing. I am tired a lot but I can take that over burning throat and chest all day and night.
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