Key takeaways
In June 2021, Pfizer halted the production of smoking cessation medication Chantix (varenicline) due to the presence of unacceptable levels of nitrosamines.
Nitrosamines are chemicals found in nature and the human body, but consuming high levels of these long-term may raise the risk of cancer.
Brand-name Chantix has been fully discontinued since its recall. But FDA-approved generic versions are available.
Save on related medications
At the end of June 2021, pharmaceutical manufacturer Pfizer announced they were stopping the global production of Chantix (varenicline). The halt of this smoking cessation pill was due to a discovery of higher levels of nitrosamines — possible carcinogens — in Chantix than what’s considered acceptable.
In the days that followed the announcement, the pause in production turned into a voluntary recall. Since then, Pfizer stopped making brand-name Chantix. But other manufacturers have stepped in with generic versions to help fill this gap.
This Chantix recall wasn’t the first time a medication was pulled due to the presence of nitrosamines. Ranitidine (Zantac), metformin, and losartan (Cozaar) have all run into similar problems in the past. But why did this happen, and is it safe to take a generic version of Chantix?
Why did Pfizer stop producing Chantix?
As part of regular safety monitoring, Pfizer discovered the presence of a nitrosamine in batches of Chantix during production. The amount of the contaminant present was higher than what’s acceptable according to FDA guidelines. Because of this, Pfizer stopped producing the medication.
Since then, Pfizer seems to have permanently stopped making Chantix. There is no word if they will resume manufacturing it in the future.
Did the FDA recall Chantix?
No. The FDA didn’t initiate the recall of Chantix. Pfizer voluntarily recalled all batches of the medication. To help alleviate medication shortages, the FDA approved the first generic varenicline in August 2021. While it may still contain nitrosamines, its levels are within acceptable FDA limits.
What are nitrosamines, and why are they bad for you?
Nitrosamines are chemical by-products found in multiple natural sources and foods, such as cured meats, dairy products, and vegetables. We’re all exposed to nitrosamines to some degree, and our bodies even make them while digesting certain foods.
The problem isn’t the chemical itself, but rather how much we consume. When large amounts of nitrosamines are consumed for long periods of time, they may raise your risk of cancer.
This link is still being investigated in humans, but animal studies suggest nitrosamines are carcinogenic (cancer-causing). There are reports that when nitrosamine is given to rats, it can cause tumors to grow in multiple organs, including the liver, kidneys, and lungs. Currently, there is no evidence to say if nitrosamines are harmful in humans or not.
The nitrosamine found in Chantix is called N-nitroso-varenicline, and it’s unique from the more well-known N-nitrosodimethylamine (NDMA) found in ranitidine and several other medications.
Does this mean Chantix may cause cancer?
We don’t know if Chantix causes cancer. N-nitroso-varenicline is still being investigated to see if there’s any link to cancer. But experts believe it may have similar risks to other nitrosamines. Long-term studies are likely being conducted to get a better answer to this question. But results of such studies wouldn’t be available for years.
How does the FDA regulate nitrosamine levels in medications?
The FDA has a set of guidelines that all pharmaceutical manufacturers must follow regarding how and when to test their medications for nitrosamines. These guidelines also have cut-off limits for each specific nitrosamine. If manufacturers discover levels of nitrosamines higher than the cut-off, they must report these findings to the FDA and stop production.
At this point, companies typically choose to voluntarily recall their contaminated medications, as seen in this case with Pfizer. If they don’t, the FDA can request the recall and pursue legal action against the manufacturer.
After this, pharmaceutical manufacturers typically take steps to lower the level of nitrosamines in their products to acceptable levels. The FDA provides detailed guidance to help manufacturers find ways to lower levels of impurities. Manufacturers can also meet with the FDA to develop strategies to help prevent future contamination.
Is Chantix back on the market?
Yes and no. Brand-name Chantix isn’t on the market right now. But there is a generic version available. Generic medications are considered equal to brand-name versions in both safety and effectiveness. They may look different than their brand-name counterparts, but you can expect the same results.
The FDA has also stated that generic Chantix that’s on the market meets the nitrosamine requirements. This means that any levels of nitrosamines in these products are within safe and acceptable levels.
Can you continue to take generic Chantix?
Yes. Since Pfizer’s initial report, the FDA has never advised people to stop using Chantix or any generic version of it. The potential risk of cancer with nitrosamines is of more concern with medications taken long-term. Chantix is typically only taken for about 3 to 6 months.
The FDA also states that the health benefits that come from quitting smoking — which includes a significantly lower risk for several cancers — far outweigh the potential risks of the nitrosamines in Chantix.
As with all medication recalls, it’s important to discuss whether you should continue taking this prescription with your healthcare provider. They’ll make a recommendation for you based on your medical history and other risk factors.
What are some alternatives to Chantix?
If you and your provider decide it’s best for you to stop Chantix, there are other options to help you quit smoking.
Nicotine replacement therapy (NRT) is one of the most accessible smoking cessation methods. Over several weeks, you slowly lower the amount of nicotine you take, gradually getting your body used to being without it. Many forms of NRT, such as nicotine patches, lozenges, and gums, are available over the counter. And, NRT is effective, boosting the success of quitting by 50% to 70%.
Bupropion SR (Zyban) is an antidepressant that is also FDA approved to help people quit smoking. It helps curb cravings and is taken for about 7 to 12 weeks. Unlike NRT, it’s only available with a prescription. In studies, bupropion is similarly effective as NRT when it comes to helping people to successfully quit smoking.
The bottom line
In June 2021, Pfizer halted the production of Chantix, a prescription medication used to help people quit smoking. This announcement was due to the discovery of potentially carcinogenic nitrosamines in the medication. Since then, Pfizer seems to have permanently discontinued the medication. But generic versions of Chantix are currently on the market.
The smoking cessation benefits of Chantix are greater than the potential risks of the contaminant. While the FDA doesn’t recommend stopping Chantix if you’re taking it, you should discuss any concerns with your healthcare provider. There are other smoking cessation options available if you and your healthcare provider decide Chantix isn’t right for you.
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