Ranitidine, widely recognized by its brand name Zantac, was a commonly used medication for relieving heartburn and acid reflux. It was also prescribed for conditions like peptic ulcer disease and gastroesophageal reflux disease. However, it was removed from the market due to concerns about a contaminating substance linked to an increased risk of cancer.
The Link Between Ranitidine and NDMA
The concerns surrounding ranitidine stemmed from the presence of N-nitrosodimethylamine, or NDMA. This compound is classified as a probable human carcinogen. Initial findings in 2019 by independent laboratories revealed concerning levels of NDMA in ranitidine products. The issue was not merely a manufacturing impurity from a single batch, but rather an inherent instability of the ranitidine molecule itself.
The ranitidine molecule can degrade over time and spontaneously form NDMA. This degradation process accelerates significantly when the drug is exposed to elevated temperatures, such as those encountered during shipping, storage, or even in a consumer’s home. Studies showed that ranitidine samples stored at 158 degrees Fahrenheit for five days exceeded the acceptable daily limit of 96 nanograms of NDMA. Even at cooler temperatures like 77 degrees Fahrenheit, NDMA levels steadily increased over time.
Regulatory Action and Market Withdrawal
Regulatory action began in September 2019 when an online pharmacy, Valisure, alerted the U.S. Food and Drug Administration (FDA) to its findings of NDMA in ranitidine. This discovery prompted the FDA to launch an investigation and issue public alerts. Several drug manufacturers responded by initiating voluntary recalls of their ranitidine products throughout late 2019 and early 2020.
The FDA continued its testing and evaluation, confirming that NDMA levels in ranitidine increased under normal storage conditions and significantly at higher temperatures. Based on these findings regarding the drug’s instability and unpredictable NDMA formation, the FDA took decisive action on April 1, 2020. The agency formally requested that all manufacturers immediately withdraw all prescription and over-the-counter ranitidine products from the U.S. market.
Cancers Associated with Ranitidine Exposure
Prolonged exposure to NDMA has been linked to an increased risk of several types of cancer. Scientific studies and legal claims have frequently cited gastrointestinal cancers. These include stomach cancer, with some meta-analyses suggesting a statistically significant increase in risk from high levels of dietary NDMA exposure.
Esophageal cancer is another gastrointestinal malignancy associated with ranitidine exposure, with some research reporting an increased risk for gastric/esophageal cancer among individuals who used prescription ranitidine. Liver cancer has also been connected, with a 2022 Taiwanese population study finding trends of increased liver cancer risk with higher ranitidine doses. Additionally, bladder cancer and pancreatic cancer have been frequently implicated in analyses of ranitidine-related NDMA exposure. While these links suggest an elevated risk, taking the drug does not guarantee a cancer diagnosis; rather, it indicates an increased potential due to carcinogen exposure.
Status of Ranitidine Lawsuits
The discovery of NDMA in ranitidine led to thousands of lawsuits filed against manufacturers. These federal cases were consolidated into a multi-district litigation (MDL) in Florida in February 2020, aiming to streamline pretrial proceedings. However, on December 6, 2022, the federal judge presiding over the MDL dismissed over 2,450 federal ranitidine cancer lawsuits. The judge’s ruling stated that plaintiffs’ attorneys failed to present sufficient scientific evidence demonstrating ranitidine could chemically transform into a cancer-causing byproduct.
This federal MDL dismissal did not conclude all ranitidine litigation. Thousands of lawsuits filed in various state courts were unaffected by the federal ruling and are progressing. Many state court cases, particularly in Delaware and Illinois, are still moving forward, with some even proceeding to trial. Pharmaceutical companies, including Pfizer and GlaxoSmithKline, have reached settlement agreements in many state-level claims.