Ranitidine is a histamine-2 blocker, which decreases the amount of acid created by the 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. The FDA and EMA investigation also led to the detection of N-nitrosodimethylamine (NDMA) levels in some Ranitidne products. Recent investigation: NDMA is a probable human carcinogen (a substance that could cause cancer). In 2019, FDA became aware of laboratory testing that found NDMA in ranitidine. Low levels of NDMA are commonly ingested in the diet, for example NDMA is present in foods and in water. These low levels would not be expected to lead to an increase in the risk of cancer. However, sustained higher levels of exposure may increase the risk of cancer in humans. The conducted laboratory tests found NDMA in ranitidine at low levels.