Zantac has low levels of cancer-causing chemical, FDA warns

U.S. health officials said Friday that they are investigating low levels of a potentially dangerous contaminant in the popular heartburn medication Zantac and related generic drugs.

The Food and Drug Administration said in a public statement it has detected a “probable” cancer-causing chemical in ranitidine, the generic term for the medication sold as both prescription and over-the-counter treatments to treat stomach acid and ulcers. The federal agency said the carcinogenic ingredient is a type of nitrosamine called N-nitrosodimethylamine, or NDMA.

The agency said patients can continue taking Zantac and similar heartburn medications for now, but patients using prescription versions who want to stop using them can consult their doctors to discuss other treatments.

Zantac maker Sanofi said in a statement it “takes patient safety seriously, and we are committed to working with the FDA.”

The FDA said NDMA is dangerous in large quantities, but the amount found in the heartburn drugs barely exceeds levels found in common foods. Agency officials said the FDA is investigating whether low levels of the carcinogen in heartburn medication is a risk to patients and will post its findings as soon as possible.

NDMA is the same chemical that has been linked to dozens of recalls of prescription blood pressure drugs in the past year, including a commonly prescribed one called valsartan. The recalled drugs, which were manufactured in China, had higher levels of the NDMA chemical than U.S. health officials deemed acceptable. The FDA is still investigating that issue and last month sanctioned a manufacturing plant in India that makes some of the ingredients used in the medications.

The FDA is responsible for ensuring that U.S. medicines are manufactured in safe, sanitary conditions. But drug regulators have struggled for years to inspect the supply chain as pharmaceutical production has spread globally.

For decades the FDA focused its manufacturing inspections on U.S. factories. But over time, most companies have moved their manufacturing overseas to take advantage of cheaper labor and materials.

Today, roughly 80% of the ingredients used in U.S. drugs are manufactured abroad, primarily in India and China, according to the Government Accountability Office.