Is fasting necessary for NDT?

[Flores59]

Is there the same fasting requirement with synthetic T4 as with NDT? The author of "Tired Thyroid" say that synthetic levothyroxine sodium requires gastric acid to cleave off the sodium ion to get thyroxine but that natural dessicated thyroid comes already as thyroxine and requires less acid. Therefore is it also necessary that NDT be taken on a empty stomach? Is there a problem with taking it with coffee and cream and waiting only 30 minutes to eat. I currently take levothyroxine at bedtime and find it better absorbed than even waiting 1 hour before breakfast and coffee. I want to switch to synthetic t4 with some NDT taken once or twice a day but I don't want to worry about long fasting periods especially if I am taking NDT twice.

[jimh111]

I don't know the answer to your specific question but I take my levothyroxine about three minutes before my porridge and have no problem. I think it may vary between individuals and more importantly how much you are eating, especially if it is a fatty meal. Coffee has a big effect on levothyroxine absorption, I don't know the mechanism. I think it's more important to avoid the coffee than food, food has less effect on absorption.

[helvella Administrator Thyroid UK in reply to jimh111]

I take my levothyroxine about three minutes before my porridge and have no problem.

And if, for some reason, you take your levothyroxine two hours before porridge, or stop having breakfast at all, don't you think you might end up absorbing more levothyroxine?

Such changes occur in many of our lives for a host of reasons. Trying to lose weight, being on holiday, being ill...

[jimh111 in reply to helvella]

No, it doesn't make a difference. I used to take it at bedtime, about five hours after dinner. I think the size of the meal and fat content has a varying effect. The important thing is to be consistent, any minor absorption issue will then be factored in.

I don't know of any studies on liothyronine or NDT absorption with food but I'd expect very little effect as the smaller T3 molecule is rapidly absorbed.

[jgelliss in reply to helvella]

Personally I think Consistency is very important . Running labs and adjusting accordingly . So if one wants to eat a snack around the meds it's advisable to be consistent and running labs if any adjustments are needed .

Consistency is the Key .

[shaws Administrator]

I think an empty stomach is the best way for hormones to be absorbed. That's why many take it when they get up with one glass of water and wait an hour before eating. It is said that food interferes with the uptake.

Excerpt:-

"WHAT ARE THE IMPLICATIONS OF THIS STUDY?

This study shows that the absorption of levothyroxine is indeed decreased when taking the hormone with breakfast. Despite an increase in TSH while taking the hormone with breakfast, the TSH remained within the normal range. Thus, while taking levothyroxine with breakfast could be an alternative regimen for patients who have difficulties taking the hormone on an empty stomach, this regimen is more likely to cause variability in the TSH level. It is still advised that patients with a history of thyroid cancer, those who are pregnant or those who are very sensitive to changes in their TSH level need to likely wait 30–60 minutes prior to taking there levothyroxine."

thyroid.org/patient-thyroid...

If you take hormones at bedtime and have had a heavy meal, you'd have to leave about 3 hours after it to take your dose.

I am not medically qualified but had undiagnosed hypo until I diagnosed myself.