Guest guest Posted October 18, 2008 Report Share Posted October 18, 2008 Kat, You wrote: > > How long before taking thyroxine should I last eat?... The best guidelines call for a minimum of two hours after and one hour before eating, and that includes beverages. On an empty stomach we only absorb about 80% of T4 anyway. With anything other than water, that can drop to 40% or less if they are together. It will be somewhere in between, the longer the wait, although I am sure the change is not linear (proportional to time). I am also skeptical of the practice of sublingual administration immediately followed by a meal. First, the main cause of the 20% that isn't absorbed under the best conditions is that globulin and albumin, the same proteins that bind T4 in the blood, diffuse into the saliva and gastric juices to bind T4 on the wrong side of the barrier. I have no idea whether that is better or worse in the thin tissue under the tongue or in the capillaries around the intestine. More importantly, I doubt that most of the medication is actually absorbed under the tongue. Your gums do not form a hermetic seal, so a good portion diffuses into your mouth to be swallowed and end up in the intestine anyway. You may not need to wait the whole hour, but I would suggest waiting at least a little while, just to be safe. I still haven't found any studies that address this question. Chuck Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You are posting as a guest. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.