Certain metformin drugs recalled due to high levels of carcinogenic contaminant

Pharmaceutical company Apotex Inc. is recalling some of its diabetes medication after some was found to have elevated levels of a contaminant which has been identified as a human carcinogen.

In a recall notice posted on Saturday, Health Canada said some lots of the company’s prescription metformin drug APO-METFORMIN ER (extended release) 500-milligram tablets were being recalled.

Metformin is a prescription drug used to control high blood sugar in patients with type 2 diabetes.

Health Canada said tests conducted by Apotex Inc. found one lot of its drugs contained N-nitrosodimethylamine (NDMA) “above the interim acceptable concentration limit.”

“As a precautionary measure, the company is also recalling eight other lots because levels of NDMA in those products may increase over time,” the recall notice reads.

Apotex Inc. has tested all of its lots and has recalled the following:

• PK3968
• PK3969
• PX5336
• PY7174
• PY7175
• RF6463
• RF6464
• RF6465
• RF6466

Health Canada said if you are taking or have taken one of the affected drugs, you should talk to your health care provider to discuss treatment options.

“You should not stop taking your metformin drug without first discussing options with your health care provider,” the release reads.

1:04 Health Canada finds second carcinogen in recalled medication

Health Canada said stopping metformin medication could lead to uncontrolled diabetes, which can cause “serious health problems” and could have long-term health impacts.

While NDMA has been classified as a probable human carcinogen, Health Canada said it is “not expected to cause harm when ingested at low levels.”

“We are all exposed to low levels of nitrosamines through a variety of foods (such as smoked and cured meats, dairy products and vegetables), drinking water and air pollution,” the recall notice reads.

The agency said a person taking a drug that contains NDMA at or below the acceptable level every day for 70 years is not expected to have an increased risk of cancer.

But, Health Canada said it has been “working to address the issue of NDMA and other nitrosamine impurities found in certain medications” since the summer of 2018.

In December, the agency said that it would be assessing the issue of NDMA in metformin products, after some metformin products available outside Canada were detected to contain NDMA above the acceptable limit.

Health Canada asked companies to test their products.

And, over the last several months, a number of medications containing metformin have been recalled.

0:44 Blood-pressure drugs containing Losartan recalled due to potential carcinogen contamination

In February, Ranbaxy Pharmaceuticals Canada Inc. recalled six lots of its prescription RAN-Metformin drug from the Canadian market after two lots were found to have NDMA levels above the acceptable limit.

A month later, JAMP Pharma Corporation voluntarily recalled all 26 lots of its prescription metformin drug from the market as a “precautionary measure.”

Health Canada said it “continues to work closely with international regulatory partners to address the issue,” and will “take action” if a new risk to Canadians is identified.