A nitrosamine impurity has been found in low levels in some ranitidine medicines, including Zantac, according to the FDA. The impurity, N-nitrosodimethylamine (NDMA), is classified as a probable human carcinogen, and is a known environmental contaminant found in water and foods, including meats, dairy products, and vegetables.

An over-the-counter (OTC) and prescription drug, ranitidine is an H2 (histamine-2) blocker that decreases the amount of acid created by the stomach. OTC ranitidine is approved to prevent and relieve heartburn associated with acid ingestion and sour stomach. Prescription ranitidine is approved for multiple indications, including treatment and prevention of ulcers of the stomach and intestines and treatment of gastroesophageal reflux disease.

In a statement, the FDA’s Janet Woodcock, MD, Director, Center for Drug Evaluation and Research, said the agency has been investigating NDMA and other nitrosamine impurities in blood pressure and heart failure medicines, Angiotensin II Receptor Blockers (ARBs), since last year. In the case of ARBs, the FDA has recommended numerous recalls as it discovered unacceptable levels of nitrosamines.

According to Woodcock, the FDA is evaluating whether the low levels of NDMA in ranitidine pose a risk to patients. In addition, the agency is working with international regulators and industry partners to determine the source of this impurity in ranitidine.

The FDA will release more information to the public about the NDMA impurity when it is available.

The FDA is urging patients to trust that their medicines are as safe as they can be and that the benefits of taking them outweigh any risk to their health. Although NDMA may cause harm in large amounts, the levels of ranitidine found by the FDA barely exceed amounts you might expect to find in common foods.

The FDA is not calling for individuals to stop taking ranitidine at this time; however, patients taking prescription ranitidine who wish to discontinue use should talk to their health care professional about other treatment options, according to Woodcock’s statement. People taking OTC ranitidine could consider using other OTC medicines approved for their condition. There are multiple drugs on the market that are approved for the same or similar uses as ranitidine.


Reference

Statement alerting patients and health care professionals of NDMA found in samples of ranitidine [news release]. Silver Spring, MD; September 13, 2019: FDA website. https://www.fda.gov/news-events/press-announcements/statement-alerting-patients-and-health-care-professionals-ndma-found-samples-ranitidine. Accessed September 13, 2019.