The following is an article about the growing risks of Chantix side effects circulated by Reuters:

WASHINGTON (Reuters) - U.S. regulators on Friday said Pfizer Inc's anti-smoking drug Chantix appears increasingly likely to be linked to serious psychiatric behavior, and called for stronger label warnings.

The Food and Drug Administration said after an analysis of reports of suicidal thoughts and behavior potentially linked to the medication, it was calling for Pfizer to strengthen the label warnings on the drug.

FDA said the drug is effective but that patients should talk to their doctors about this new safety information.

The drug has been prescribed to about 4 million people in the United States since approval in 2006, according to Pfizer.

Additional comments:

Chantix is one of the most recent non-nicotine stop-smoking treatments on the market. It was approved by the FDA in 2006. After its launch, some of the more than 5 million patients who used the drug began to report adverse side events, including anxiety, other serious psychiatric changes, and "vivid" and "unusual" dreams. Because of these reports, Pfizer has strengthened the warning label for Chantix. Last week's FDA announcement formalized more specific safety warnings for the drug's label.

Chantix's biggest advantages against Nicoderm and most other smoking-cessation agents is that it contains no addictive nicotine, which is currently the predominant "solution" for smoking cessation on the market. There has been no reporting about chantix drug interaction with other pharmaceuticals, beyond what is already known in the medical community.

In a 2007 year ending conference call, Pfizer's executives did not disclose what amount of the potential market for Chantix has a psychiatric illness that would prevent it from using Chantix. According to experts, Chantix is Pfizer's most important new drug at the moment. Sales of the drug have grown much faster than experts have expected. Growing 312% year over year to $280 million worldwide.