The U.S. Food and Drug Administration (FDA) has recalled several drug products containing the active ingredient valsartan, which is widely used in China, over fears it might be contaminated with a probable human carcinogen known as N-nitrosodimethylamine (NDMA).
The announcement has revived concerns surrounding the safety of important drugs, many of which come from countries with lax safety and purity standards.
Contamination is believed to be a result of changes made to the way valsartan is manufactured.
The recalled valsartan was made in China by Zhejiang Huahai Pharmaceutical Co. Ltd.. In the United States, the medicine is distributed by Major Pharmaceuticals; Teva Pharmaceutical Industries Ltd.; and Solco Healthcare.
Dr. Janet Woodcock, director of the F.D.A.’s Center for Drug Evaluation and Research, said:
“We have carefully assessed the valsartan-containing medications sold in the United States, and we’ve found that the valsartan sold by these specific companies does not meet our safety standards. That is why we’ve asked these companies to take immediate action to protect patients.”
On July 13, red flags were raised after FDA officials found traces of NDMA in valsartan, a medicine prescribed to treat high blood pressure and heart failure. 
A week before the agency’s July 15 recall announcement, 2,300 batches were recalled across Germany, Norway, Finland, Sweden, Hungary, the Netherlands, Austria, Ireland, Bulgaria, Italy, Spain, Portugal, Belgium, France, Poland, Croatia, Lithuania, Greece, Canada, Bosnia and Herzegovina, Bahrain, and Malta.
The potentially cancer-causing substance was once used to make liquid rocket fuel and antioxidants. The compound is currently only used for research purposes.
The FDA is working to determine the levels of NDMA in the recalled batches of valsartan. An assessment is also underway to understand the type and scope of potential harm to patients who have been taking the drug.
Per the FDA’s instructions, patients taking valsartan should look at the manufacturer’s name on the label of their prescription bottle to determine if it’s part of the recall. If the information is not printed on the label, patients should contact their pharmacy. 
Additionally, people who take a drug containing valsartan should continue taking the medication until a substitute becomes available. Their healthcare provider should be able to offer an alternative, including valsartan distributed by Sun Pharma, Mylan, Jubiliant, Aurobindo and Hetero, according to Fore Pharma, which are not subject to the recall, the FDA said.
John Brito, of the research market firm Fore Pharma, said:
“The recall is huge, based on the volume and the large number of patients it could have impacted, but we believe this could get offset by other players stocking up in short term. Switch options are available for a hypertension patient.”
SomTribune (featured image source)