Many people don’t realize that coffee and several other foods may partially block absorption of the thyroid medicine Synthroid (Benvenga et al, Thyroid, March 2008). Over-the-counter medicines such as calcium carbonate (Tums, for example) can also interfere with levothyroxine absorption (Singh, Weisler & Hershman, Thyroid, Oct. 2001). This doesn’t seem to be due to reduced acid in the stomach, though: famotidine (Pepcid) and esomeprazole (Nexium) both are more powerful acid suppressors than calcium carbonate, and neither one alters levothyroxine absorption (Ananthakrishnan et al, Thyroid, May 2008).
Does All Thyroid Medicine React to Coffee?
Q. I’ve been on levothyroxine for years to treat hypothyroidism. I did not know that “take on an empty stomach” meant no coffee as well as no solid food.
When I learned that, I also read that with Tirosint you could have caffeine and even solid food. I persuaded my doctor to switch me to Tirosint. Now I don’t have to wait an hour after taking my thyroid medicine before having breakfast.
Tirosint in the Morning:
A. Tirosint capsules were developed to be better absorbed than levothyroxine tablets such as Synthroid. This medicine can be taken with breakfast and there is no effect on absorption (Cappelli et al, European Journal of Endocrinology, Jan. 2014). In general, this soft-gel form of thyroid medicine and a liquid form are better absorbed and less likely to interact with food than the usual levothyroxine pills (Fallahi et al, Expert Opinion on Drug Delivery, May 2017).
You pay for this convenience, of course: Tirosint costs more than Synthroid and about ten times as much as generic levothyroxine.
You will find greater detail about when and how levothyroxine tablets should be taken for greatest efficacy in our Guide to Thyroid Hormones.
You may also be interested in our recent interview with Dr. Antonio Bianco, one of the country’s leading biomedical researchers on thyroid disorders and thyroid patient advocate Mary Shomon. It is Show 1096: What You Need to Know about Treating Thyroid Disease.