In April of 2022, Pfizer voluntarily recalled five batches of the drug because of the presence of a nitrosamine, NNitroso-quinapril. Testing found that the amount of nitrosamines was above the acceptable daily intake level (all humans are exposed to nitrosamines up to a certain daily level by cured and grilled meats, water, dairy products, and vegetables) set by the U.S.'s Food and Drug Administration (FDA). Though long-term ingestion of NNitroso-quinapril potentially might cause cancer in some individuals, there is not believed to be an imminent risk of harm.