Varenicline

Varenicline is the chemical name of the drug sold under the trade name of Chantix in the United States, and Champix in Canada, Europe and other countries, marketed by Pfizer.

In November 2007 the FDA reported that it had received numerous reports that patients using Varenicline experienced serious side effects, the most notorious of which was suicidal behaviour. While some thought to associate this with nicotine withdrawal, it should be noted that

• not all of those exhibiting suicidal behaviour had actually stopped smoking
• lots of people exhibit nicotine withdrawal by other methods and don't commit suicide

In 2009, the FDA required the strongest warning possible on a medicine to be placed on Varenicline

Other (non-trivial) symptoms reported:

• Nausea
• Headaches
• Insomnia/nightmares
• Increased danger to those with cardiovascular disease