Following an industry-wide recall of ranitidine-containing medications due to a detection of a contaminant known as N-Nitrosodimethylamine (NDMA), the regulator found the same potentially carcinogenic substance in nizatidine drugs. Nizatidine is chemically similar to ranitidine.

After the Ministry of Food and Drug Safety detected NDMA in ranitidine, the main ingredient for stomach medicines, it collected nizatidine drugs to test them for any harmful chemical.

The authorities have completed the test and the results showed that some of the collected drugs contained NDMA.

Nizatidine is a class of H2-receptor antagonists (therapies for gastric ulcer and duodenal ulcer), just as ranitidine is.

Japan’s Ohara Pharmaceutical voluntarily recalled (Class 1) nizatidine medicines after the health authorities found the levels of NDMA exceeding the standard levels.

NDMA is an impurity defined by the WHO’s International Cancer Research Institute (IARC) as a potentially cancer-causing substance to humans, categorized in Group 2A.

The ministry said it collected 95 nizatidine-containing drugs. As some of them had NDMA, the ministry said it would collect all "tidine"-class medications for the detection of the harmful substance.

Kim Nam-soo, director of the Pharmaceutical Product Management Division at the Food and Drug Safety Ministry, said, “We’re monitoring ranitidine first. But as we don’t know NDMA will be detected in which other drugs, we will have to look into the entire raw materials.”

The food and drug safety ministry plans to announce the final results of the nizatidine drug tests by next week, and order a recall on medications contaminated with NDMA.