Strangely enough, I keep taking it without an empty stomach (I just can't seem to wrap my head around this seemingly simple request!!!) and I am still on the hyper side of normal (range 11-22 at 24- still haven't figured out what units these are in).
Thyroxine is absorbed in the small intestine NOT the stomach. Specifically the jejunum and ileum and the duodenum. If food is added then;
1.-the amount of time the thyroxine spends in the small intestine is greatly decreased as food increases gastric motility ie. the speed that gastric contents pass through the gastrointestinal tract including the small intestine.
2.-the thyroxine competes with other nutrients for absorbtion in the small intestine
"Fasting will only increase the extent of absorption, whereas malabsorption will only cause a decrease in absorption." (Monthly Index of Medical Supplies [MIMS] 2007) [MIMS is a medical resource available to health professionals in Australia - not sure about other countries]
The prescribing info for Synthroid states that only 40-80% of the thyroxine you ingest is actually absorbed under the recommended conditions ie. in the absence of food.
Example; If you normally take 100mcg Synthroid per day then if you take your medication as directed, 30 to 60 minutes before food then your body is getting a true benefit from between 40 and 80mcg.
**** IF**** you don't take Synthroid on an empty stomach then you could be getting less than 40mcg per day. WHOA - that's not much!!!
So if you are wondering why your Synthroid is not having as much effect as you anticipated OR the effect is fluctating THEN start taking it consistently 30-60 minutes before food!!!!!!!! Just do it - you'll feel better!!!!!
Another aspect is that you might find you could lower your dose if you took your dose correctly (could this result in a lower cost prescription for you guys and gals in America-not sure how it works over there?)
Synthroid's website has some really good, easy to read and understand educational stuff for everyone. Go have a look even if you take levothyroxine or some other brand.
It pays to know what you are taking and how it works. Doctors just don't seem to have the time to explain it all in detail to us - though I'm sure if we all understood we would make a better go of it.
The Content on this Site is presented in a summary fashion, and is intended to be used for educational and entertainment purposes only. It is not intended to be and should not be interpreted as medical advice or a diagnosis of any health or fitness problem, condition or disease; or a recommendation for a specific test, doctor, care provider, procedure, treatment plan, product, or course of action. MedHelp is not a medical or healthcare provider and your use of this Site does not create a doctor / patient relationship. We disclaim all responsibility for the professional qualifications and licensing of, and services provided by, any physician or other health providers posting on or otherwise referred to on this Site and/or any Third Party Site. Never disregard the medical advice of your physician or health professional, or delay in seeking such advice, because of something you read on this Site. We offer this Site AS IS and without any warranties. By using this Site you agree to the following Terms and Conditions. If you think you may have a medical emergency, call your physician or 911 immediately.