The European Medicines Agency is reviewing medicines containing valsartan supplied by a facility in China after a potentially cancer-causing impurity was detected.

The company Zhejiang Huahai found N-nitrosodimethylamine (NDMA) in the valsartan active substance supplied to manufacturers producing some of the valsartan medicines available in the European Union.

These are used to treat people with high blood pressure, to reduce complications such as heart attack and stroke, and also those who have had a heart failure or a recent heart attack.

The presence of NDMA - which is classified as a probable human carcinogen based on lab tests - was unexpected and is thought to be related to changes in the way the active substance was manufactured, the EMA said.

National authorities across the EU are now recalling medicines containing valsartan supplied by Zhejiang Huahai while a review investigating levels of NDMA is undertaken.

In the UK, the MHRA said it is advising pharmacies to recall all batches of valsartan containing medicines made by Dexcel Pharma and Accord Healthcare (previously known as Actavis Group) as a precaution.

“People taking valsartan medication affected by this recall are advised to not stop taking their medication, but to speak to their doctor or healthcare professional who can advise on alternative treatment,” said Dr Sam Atkinson, MHRA’s Director of the Inspection, Enforcement and Standards Division.

“We will communicate the outcome of our investigations and ensure that any other affected products are recalled,” he added.