The World's #1 Quit Smoking Community

Have questions? Contact us.

July 15 2010


Fred Kelley,

Chantix (varenicline) is the latest prescription medication designed to help adults quit smoking. It is also sold under the name Champix in Canada, Europe and other countries. Chantix is not a nicotine replacement therapy (NRT) product like the nicotine patch or nicotine gum that have been on the market for many years. Instead, Chantix is believed to work by blocking nicotine from reaching the receptors in the brain that are normally associated with cravings and addiction to nicotine. In clinical studies, patients using Chantix reported that their urge to smoke was reduced. In some of those same studies, as high as 44% of patients using Chantix abstained from smoking.

How does Chantix work?

To understand the way Chantix works, it’s important to understand how nicotine works.

Nicotine affects the brain. That’s one reason why it is so addictive. Nicotine enters the body and travels to the brain where it attaches itself to tiny receptors. This tells a different part of the brain to release dopamine, a neurotransmitter commonly associated with the pleasure response in the brain. The feelings of enjoyment provided by dopamine reinforce behaviors and motivate individuals to proactively perform certain activities, such as smoking.

When dopamine levels quickly drop, smokers often feel bad and experience cravings for another cigarette.

What Chantix does is attach to the same nicotine receptors, preventing dopamine release. Thus, while smoking introduces nicotine into the body, the nicotine is unable to cause dopamine release. No dopamine, no pleasure, no desire for more nicotine.

Since Chantix is attached to the nicotine receptors, there is some stimulation, but at much lower levels than that caused by nicotine. The stimulation “stays on” all the time since Chantix is taken daily for an extended period of time, creating a shield from the roller coaster ride of nicotine addiction. Smokers have fewer cravings and experience less of the typical withdrawal symptoms they might experience without the use of Chantix.

Clinical Trials of Chantix

Chantix was tested and studied in six separate trials, involving 3659 smokers who smoked 10 or more cigarettes per day.

Two of the studies were double-blind, meaning that neither the personnel administering the medication, nor the patients knew which medication each patient was receiving. This type of study removes any bias that might creep in when one or more parties has preconceived expectations about a particular pill. The two studies compared the use of placebo (sugar) pills, Zyban (bupropion, another prescription smoking cessation medication) and Chantix. Both studies had nearly identical results, with 44% of patients treated with Chantix abstaining from smoking during weeks 9 through 12 of the study. Patients given the Zyban had an abstinence rate of 30%. Patients treated with the placebo had abstinence rates of 17% in the first study and 18% in the second.

Five of the six studies examined long-term abstinence rates, with 40 weeks of follow-up. In all of the studies, patients treated with Chantix were more likely to remain smoke-free after the treatment ended than those treated with the placebo or Zyban.

A sixth study was conducted to determine if patients would benefit from an additional 12 weeks of treatment after the initial 12 week treatment period. The study found that patients who used Chantix for the additional 12 weeks were more likely to abstain from smoking during the 12 week treatment period, and were more likely to remain smoke free after the treatment ended.

Chantix Side Effects

As with most prescription and non-prescription medication, Chantix may cause side effects.

Chantix patients have reported a variety of side effects including nausea, headache, sleep difficulties (insomnia, vivid or strange dreams), constipation and gas. If these symptoms persist or if they bother you, let you doctor know.

Other more serious side effects such as suicidal thoughts, depression and behavioral changes have been reported as well. It’s important to report these symptoms to your doctor. Your family or others around you may notice these effects before you notice them yourself.

Before taking Chantix, tell your doctor about any history of depression or other mental health problems, since these may worsen when taking Chantix.

Use caution while driving or operating machinery until you know how Chantix may affect you.

Chantix should not be taken with other quit smoking medications.

If you have a kidney disorder or receive dialysis, you may need a lower dose of Chantix.

If you are pregnant, plan to become pregnant, or if you take insulin, asthma medicines, or blood thinners, tell your doctor before you start taking Chantix.

Dosage Info

Smokers receiving a Chantix prescription should first set a quit date upon which they will completely stop smoking. They should begin taking Chantix one week prior to their quit date.

The pills should be taken after a meal, with a full glass of water.

The recommended dose of CHANTIX is 1 mg twice daily following a one week introduction to the medication:

Days 1 to 3: 0.5 mg once daily
Days 4 to 7: 0.5 mg twice daily
Day 8 to end of treatment: 1 mg twice daily

If the patient cannot tolerate any adverse effects of Chantix they may have their dose reduced temporarily or permanently.

Treatment with Chantix should be for 12 weeks. After the initial 12 weeks, patients who have remained smoke free may receive an additional 12 week treatment to increase long-term smoking abstinence.

Patients who are not able to successfully quit smoking during the initial 12 weeks of treatment, or who relapse after treatment, should be encouraged to try again once they have addressed the reason their first attempt was not successful.

As with most any smoking cessation method or product, Chantix users are more likely to quit smoking successfully if they are self-motivated to end their habit, and if they are given additional support and advice. Ask your doctor for their help and suggestions to make quitting easier and more successful.


While the results from Chantix are promising (up to 44% quit rate), it still won’t help every smoker to quit. Nothing, short of death, will force a smoker to end their habit. Sorry, but their is no magic pill. Influencing and changing the way your brain reacts to nicotine can improve your chances of quitting smoking permanently. But you must first want to quit, and be willing to stick it out, even if you experience some discomfort. Remember, too, that smoking is more than just a nicotine addiction. As a smoker, you have created a life that tends to revolve around your next cigarette. To quit, you’ll need to change and disrupt your routine, stop doing certain behaviors that tend to trigger a desire for a cigarette such as getting a drink at a bar, and perhaps most important, you must believe that you can actually quit smoking.

About the Author