New Study May Spell Trouble for Zantac Manufacturers

Did Zantac release a carcinogen in your stomach?

The Journal of the American Medical Association (JAMA) has published a new study on Zantac. It may impact ongoing Zantac lawsuits. The popular heartburn medication was pulled from U.S. shelves in April 2020. Manufacturers removed it from stores after discovering a carcinogen in the drug. Now, manufacturers are facing hundreds of consumer lawsuits and may face more in the near future.

A carcinogen is a substance or material capable of causing cancer. The carcinogen found in Zantac is known as n-nitrosodimethylamine (NDMA).

Most pills are composed of the active ingredient plus other materials that form the body of the pill. The manufacturing process contains a number of steps at which a carcinogen could be introduced to the final pill. Regulators initially attributed the carcinogen in Zantac to contamination during this process.

However, the new JAMA study shows the drug itself may break down after being released from the pill. As the ranitidine molecule breaks down in the stomach, it can release a carcinogen.

Study: Zantac May Produce Carcinogen in the Human Stomach

Researchers from Memorial Sloan Kettering and Valisure, an online pharmacy, executed the study. They investigated the behavior of ranitidine, Zantac's active ingredient. According to experts, ranitidine's structure allows the release of NDMA as it breaks down. The study sought to understand how this tendency might play out in the human body.

When ingested, Zantac tablets experience the environment of the human stomach. Thus, researchers tested the drug's behavior using simulated stomach fluid. They used several different conditions in an attempt to account for person-to-person variations. Their results may give consumers cause for concern.

Under conditions possible in the human stomach, a 300 mg Zantac tablet yielded 612,000 ng of NDMA. For reference, the U.S. Food and Drug Administration (FDA) has set a maximum daily exposure level of NDMA in drugs: 96 ng.

In other words, one Zantac tablet generated more than 6000x the safe level of NDMA.

Zantac generated less NDMA in other conditions also possible in the human stomach. But, all tested conditions produced NDMA in excess of the amount considered safe.

Study Results Contradict FDA's Past Statement

Before Zantac was pulled from shelves, the FDA spent time investigating the drug. The FDA's NDMA Press Announcement Page lists 18 updates from September 2019 to April 2020. One of those updates states:

The results of these tests showed no additional NDMA generated in the stomach.

This directly contradicts the results of the JAMA study. There are a number of potential explanations for these differing results:

  • The FDA and JAMA studies used different test conditions.
  • The instruments used to measure NDMA were miscalibrated in one of the studies.
  • Human error led to incorrect results in one of the studies.

Other researchers will have to repeat these experiments to determine which results are valid. Until then, experts agree Zantac should not return to shelves.

Study Results May Factor into Ongoing Zantac Legal Battle

There are currently more than 500 Zantac cancer lawsuits pending. Plaintiffs have made a number of allegations in these lawsuits. Among those allegations, consumers claim manufacturers knew the drug could form NDMA. The JAMA study results seem to support this point, which may prove problematic for manufacturers.

Given the conflicting information from the JAMA study and FDA tests, only time will tell how this issue may develop in court. In the meantime, if you or a loved one developed cancer after taking Zantac, you should consider taking legal action. You can sign up for a free, no-obligation Zantac cancer legal consultation here.

Authored by Katy Moncivais, Ph.D.Medical Editor
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Katy Moncivais holds a Ph.D. in Biomedical Engineering from The University of Texas at Austin. She’s an experienced Regenerative Medicine Consultant with a demonstrated history of working in the hospital & healthcare industry. Skilled in adult stem cells, medical devices, biomechanics, bacterial and mammalian cell culture, and regenerative medicine, she provides guidance on an array of topics affecting consumers. In her role at, Dr. Moncivais works alongside the writing and research staff to help deliver fact-based news stories to consumers. Her unique professional history alongside her rigorous educational background allows her to contribute to a variety of consumer-focused topics with a fresh perspective. In addition, Dr. Moncivais reviews portions of medically driven content to ensure scientific accuracy.
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