The FDA published interim acceptable intake levels of nitrosamine impurities in angiotensin II receptor blockers (ARBs) that manufacturers may use to ensure finished drug products are safe for patients. The agency evaluated safety data for carcinogens N-Nitrosodimethylamine (NDMA) and N-Nitrosodiethylamine (NDEA) and established interim acceptable intake levels in the ARB class. The impurities are known to exist in certain valsartan, irbesartan and losartan-containing products, which – along with some active pharmaceutical ingredients used to manufacture them – were previously recalled from the U.S. market. The agency is using its interim limits as guidelines for manufacturers to conduct voluntary recalls in the event lab testing confirms the presence of nitrosamine impurities in finished drug product. The FDA said it is working with industry and international regulators to ensure that products entering the market do not contain the impurities but is tolerating impurities below the interim levels for a short time to avoid a possible shortage of ARBs. Manufacturers were advised to measure any evidence of impurities in drug substances and products using the gas chromatography/mass spectrometry (GC/MS) headspace, combined GC/MS headspace or combined GC/MS direct injection method and to take appropriate action to ensure product safety. Because some ARB products do not contain NDMA or NDEA impurities, prescribers and pharmacists also may be able to offer patients alternative medications that are not affected by the recalls. The FDA posted a table of the interim NDMA or NDEA limits in recalled drug products on its website at http://bit.ly/2EAON4T.