Following an earlier recall for its smoking cessation medication Chantix, Pfizer (PFE) has expanded the recall to include four more lots of the drug because it also may contain N-nitroso-varenicline – a substance that could cause cancer – above the acceptable daily intake levels set by the Food and Drug Administration.

N-nitroso-varenicline is commonly found in water and food, including cured and grilled meats, dairy products, and vegetables. N-nitroso-varenicline is a possible carcinogen that, with long-term ingestion, could potentially increase the risk of cancer.

However, Pfizer said there is no immediate risk associated with people taking Chantix as the health benefit of stopping smoking outweighs the cancer risk of the impurity.

The Chantix medication that is being recalled helps people quit smoking and is intended for short-term use.

The recalled lots were distributed nationwide to wholesalers and distributors in the U.S. and Puerto Rico from June 2019 to June 2021. The medication was prescribed to consumers in 0.5 mg/1 mg tablets.

A full list of all the Chantix products recalled and labels can be viewed here.

Consumers that are taking Chantix should consult with their healthcare provider or pharmacy to determine if they have the affected product lots.

If a consumer has the recalled medication in their possession, they should contact Stericycle Inc. at 1-888-276-6166, Monday through Friday from 8 a.m. to 5 p.m. ET for instructions on how to return the product and obtain reimbursement for the cost of the medication.

To report adverse effects or a product complaint from the medication, contact Pfizer Drug Safety at 1-800-438-1985, option 1, 24 hours a day, seven days a week.

Pfizer said it has not received any reports of adverse events related to the recall of the medication.

As of Tuesday at 10:43 a.m. ET, shares of Pfizer were trading at $50.36, up $1.45, or 2.96%.

pfizer logo The Pfizer logo is pictured here. Photo: AFP / Don EMMERT