When several heart medications were found to be contaminated with varying levels of two compounds that are suspected of being human carcinogens, most reports confidently named valsartan as the culprit. Several lots of medications containing valsartan manufactured primarily in Chinese laboratories were found to contain trace amounts of compounds known as NDMA and NDEA. Subsequent testing lead to recalls being issued in both the United States and Canada while patients and their doctors worked to determine whether or not their medications came from tainted batches and how to replace them.
Last month, the FDA recalled yet another heart medication over the risk of chemical impurities, but this time the medication is not based on valsartan.
Heart patients taking medications based on irbesartan are advised to speak with their medical care providers over concerns that various lots of the drug may contain an impurity that poses a small cancer risk. According to CNN, the FDA has stated that recalled lots will have “Westminster Pharmaceuticals” and “GSMS Inc.” printed on the label.
The recalled lots have tested positive for NDEA; one of the same compounds found in the contaminated valsartan lots. As a result, the FDA has begun testing of all drugs that act as ARBs, or angiotensin II receptor blockers. Zhejiag Huahai Pharmaceuticals is a known producer of multiple ARBs, and while the company now finds itself on an import blacklist that disallows any of its medications from entering the United States, that action does not account for any ARBs that may have already made it into the ports and onto pharmacy shelves. It also does not take into account the fact that up until the irbesartan recall was issued, all attention had been focused on valsartan shipments.
It should be noted however that while the situation should be treated with its due level of seriousness, the recalls actually only affect about 1% of the irbesartan drugs on the US drug market. However, given the number of Americans being treated for heart problems, even 1% represents a number that is too high to ignore.