Varenicline tartrate, marketed as Chantix™ by Pfizer, is a type of prescription stop-smoking pill that lessens the effects of nicotine on the brain’s chemicals, making it easier for some users to quit smoking. Smokers start taking the stop-smoking pills at least one week prior to the actual date they wish to quit. During the time they are both taking the stop-smoking pills and smoking, the drug interacts with their bodies in such a way that they no longer enjoy smoking but still having some feelings of relaxation, which can lessen the anxiety associated with smoking cessation. The combination of these two interactions on the body is what helps the person to quit smoking.
There are receptors in the brain called nicotinic acetylcholine receptors. When a person smokes, the nicotine inhaled attaches to these receptors. The receptors then send a chemical message to release dopamine, a brain chemical that causes a person to feel pleasure, thus making the person want to continue smoking. The burst of pleasure fades within minutes, which leads the person to smoke more. This is what can lead to nicotine addiction.
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Stop-smoking pills such as varenicline tartrate latch onto the nicotinic acetylcholine receptors and interact with them in two ways. First, they activate the receptors but to a lower degree than nicotine. Without smoking, the person still gets a slight feeling of relaxation, which can lessen the effects of nicotine withdrawal. The person also does not have a direct association between inhaling the cigarette and the feeling of pleasure.
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Second, stop-smoking pills block the receptors from responding fully; when the person smokes, the pleasurable sensations they anticipate do not come. The experience of smoking is no longer as satisfying for many users. This lack of joy can decrease stop-smoking pill users’ desire to smoke, thus making it easier for them to quit.
Chantix™ can be combined with an overall smoking cessation program that includes counseling and support, but it is not to be taken while using nicotine patches or gum. Insulin, asthma medications and blood thinners may work differently when taken with varenicline tartrate. Common side effects include dry mouth, intense and strange dreams, constipation, and nausea. The use of Chantix™ has been linked to suicide attempts, suicidal thoughts, increased depression, hostile behavior, aggression, manic thoughts, anxiety, anger, paranoia and hallucinations in some patients. People who experience this type of reaction should stop taking the medication and talk to a medical professional.