logoThe People's Perspective on Medicine

Could Heartburn Medicine Clash With Thyroid Pills?

PPI drugs for acid reflux like Nexium or Prilosec may interfere with absorption of thyroid pills such as Levoxyl or Synthroid.
Could Heartburn Medicine Clash With Thyroid Pills?

If you have an underactive thyroid gland, you know how important it is to take your thyroid pills on a regular basis. You may have even heard that you should not take your levothyroxine (Euthyrox, Levothroid, Levoxyl, Synthroid, Unithroid) with coffee. But what about other medications? One reader wondered about heartburn medicine.

Will a PPI Interfere With Absorption of Thyroid Pills?

Q. I have been taking a PPI daily for many years to treat Barrett’s esophagus. During all that time, I have been struggling with symptoms of low thyroid activity, even though I take my thyroid pills conscientiously. My TSH is elevated and my doctor keeps increasing my dose of levothyroxine. Do you have any suggestions?

A. There is a strong likelihood that the PPI (proton pump inhibitor) you are taking for acid reflux is interfering with absorption of your thyroid medicine (Clinical Drug Investigation, March 2015). 

Maximizing Absorption of Thyroid Pills:

There are two possible solutions to this problem. First, your gastroenterologist could find a different way to treat the Barrett’s esophagus. Alternately, your doctor could prescribe a soft-gel form of levothyroxine (Tirosint). Unfortunately, Tirosint can be pricey if your insurance does not cover it.

In addition to proton pump inhibitors such as esomeprazole (Nexium), lansoprazole (Prevacid) or omeprazole (Prilosec), certain other medicines may interfere with thyroid pills. Specifically, iron, calcium and estrogen can lead to elevated TSH (Clinical Endocrinology, Jan. 2015).

Learn More:

You can learn more about this and other interactions with levothyroxine in our eGuide to Thyroid Hormones. You may also wish to listen to our most recent interview on treating thyroid problems. It is Show 1196: What to Do If Thyroid Treatment Doesn’t Work for You.  In addition, Show 1179: What Should You Do About Digestive Distress? has information on treating Barrett’s esophagus.

Rate this article
3.9- 28 ratings
About the Author
Terry Graedon, PhD, is a medical anthropologist and co-host of The People’s Pharmacy radio show, co-author of The People’s Pharmacy syndicated newspaper columns and numerous books, and co-founder of The People’s Pharmacy website. Terry taught in the Duke University School of Nursing and was an adjunct assistant professor in the Department of Anthropology. She is a Fellow of the Society of Applied Anthropology. Terry is one of the country's leading authorities on the science behind folk remedies. .
  • Trifiro G et al, "Drug interactions with levothyroxine therapy in patients with hypothyroidism: Observational study in general practice." Clinical Drug Investigation, March 2015. DOI: 10.1007/s40261-015-0271-0 [Indexed for MEDLINE]
  • Irving SA et al, "Drugs that interact with levothyroxine: an observational study from the Thyroid Epidemiology, Audit and Research Study (TEARS)." Clinical Endocrinology, Jan. 2015. DOI: 10.1111/cen.12559
Join over 150,000 Subscribers at The People's Pharmacy

We're empowering you to make wise decisions about your own health, by providing you with essential health information about both medical and alternative treatment options.