Pfizer has voluntarily recalled Accuretic (quinapril HCl/hydrochlorothiazide), and two of its generic versions, due to high levels of a nitrosamine, a potential cancer-causing impurity.

The US drugmaker recalled six lots of its blood pressure drug, one lot of quinapril and hydrochlorothiazide tablets and four lots of quinapril HCl/ hydrochlorothiazide tablets.

Exposure to nitrosamines above Acceptable Daily Intake (ADI) levels for prolonged durations may increase the risk of developing cancers.

However, there is no immediate risk to patients taking the drug, said Pfizer.

Accuretic and its generic versions are indicated for lowering the blood pressure (hypertension), to reduce the risk of cardiovascular events, including stroke and myocardial infarctions.

The safety profile of the products has been established through more than 20 years of marketing authorisation and a large-scale clinical programme.

Pfizer stated that it did not find any reports of adverse events related to the recalled drugs, and the benefit/risk profile of the products is positive based on current data.

The company advised patients currently taking the hypertension drug to consult with their doctor to explore alternative treatment options.

Earlier this month, Pfizer Canada has recalled Accuretic due to the presence of the same N-nitroso-quinapril impurity.

The company then assure patients that they can continue their medication and are not needed to return the drug, but has urged patients to consider alternatives.

In September last year, Pfizer has recalled all lots of its anti-smoking treatment Chantix due to the presence of cancer-causing agent nitrosamines in elevated levels.

Chantix was approved in the US as a prescription drug used for 12 to 24 weeks to help adults aged 18 years and older to quit smoking.