TORONTO -- Ranbaxy Pharmaceuticals is the latest drug maker to pull all of its prescription ranitidine products from the Canadian market as Health Canada continues its investigation into an impurity known as N-nitrosodimethylamine (NDMA) in the drugs.

According to the latest recall notice from Health Canada, the drug maker pulled all lots of its prescription ranitidine products as a precautionary measure.

Ranbaxy Pharmaceuticals is the latest drug company to join the precautionary recall. Last Friday, Dominion Pharmacal, Laboratoire Riva Inc., Pharmascience Inc. and Vita Health Inc. also recalled batches of their prescription and over-the-counter products.

The recalls are part of an ongoing recall of ranitidine products, commonly used for treating and preventing ulcers in the stomach and intestines. The drugs are also used to treat acid reflux and heartburn associated with acid indigestion and sour stomach.

Last month, Health Canada announced it had joined forces with the U.S. Food and Drug Agency and the European Medicines Agency to investigate levels of NDMA in the drugs.

NDMA is classified as a probable human carcinogen, which means long-term exposure to unsafe levels could increase a person’s risk of cancer, according to a Health Canada release. It is not expected to cause harm when ingested at very low levels.

Health Canada has been working to address the issue of NDMA and similar impurities found in certain blood pressure medications since 2018.

According to Health Canada, individuals taking a prescription ranitidine drug, including a recalled product, should not stop taking it unless they have spoken to their health-care provider and obtained alternative treatment.

A full list of affected products can be found on Health Canada’s website.

- With files from Jeremiah Rodriguez