Pfizer also asked wholesalers and distributors to stop the use and distribution of Chantix tablets immediately. Long-term ingestion of N-nitroso-varenicline may be associated with a theoretical potential increased cancer risk in humans, but there is no immediate risk to patients taking this medication, according to a release from Pfizer. This isn’t the first time the drug has been recalled because of impurities. In June, the company announced it was stopping global shipments after testing found nitrosamine. In July, the company recalled 12 lots of Chantix, and 4 additional lots were recalled in August. A “lot” is a batch or a specified portion of a batch of a medication and is identified with a lot number so that manufacture, processing, packing, holding, and distribution can be tracked. Chantix isn’t the only medication to have issues with nitrosamine impurities that have led to lot recalls. The U.S. Food and Drug Administration (FDA) provides information and guidance for both doctors and patients on products that have been found to have impurities. Everyone is exposed to some nitrosamines; they’re common in water and foods such as grilled meats, dairy products, and vegetables, according to the FDA. NDMA may increase the risk of cancer if people are exposed to it at above acceptable levels and over long periods of time. A person might take a drug that contains nitrosamines at or below the acceptable daily intake limits every day for 70 years and not be expected to have an increased risk of cancer, said the agency. Patients taking varenicline should continue taking their current medicine until their pharmacist provides a replacement or their doctor prescribes a different treatment, according to the FDA’s statement. The health benefits of stopping smoking outweigh the theoretical potential cancer risk from the nitrosamine impurity in varenicline, said the statement. Patients with Chantix Tablets should contact Stericycle Inc. at 888-276-6166 (Monday–Friday, 8 a.m.–5 p.m. ET) for instructions on how to return their product and obtain a monetary reimbursement.