Pfizer has recalled all lots of anti-smoking treatment Chantix due to high levels of cancer-causing nitrosamines, reports Reuters.
Pfizer paused distribution in June and asked wholesalers and distributors last week to stop use and distribution immediately.
Patients taking Chantix face no immediate risk, according to the company, but they should consult healthcare providers about alternative treatment options.
The FDA approved Chantix in 2006 as a quit-smoking aid.