As many as 2 million patients worldwide likely have been exposed to a class of generic blood-pressure drugs containing probable human carcinogens, the FDA estimates in a report from The Wall Street Journal.
More than half of the patients who were taking the common generic drugs — valsartan, irbesartan and losartan — were in the U.S.
Not all generic products were affected, nor are the brand-name versions of the blood-pressure medication.
The FDA learned last summer that some generic versions of the blood pressure drugs, called angiotensin II receptor blockers, contained nitrosamine impurities. The impurities, N-Nitrosodimethylamine and N-Nitrosodiethylamine, are likely carcinogenic.
The discovery initially prompted recalls of just a few drugs containing the impurity, but the list of recalls has grown. The most recent recall was announced last week.
The FDA has been investigating the root cause of the issue.