Drug Information

Varenicline (Champix) for Quitting Smoking

Varenicline (Champix) for Quitting Smoking

British Columbia Specific Information

The B.C. Smoking Cessation Program helps people stop smoking or using other tobacco products by assisting them with the cost of nicotine replacement therapies. The Program covers 2 types of prescription smoking cessation drugs: bupropion (Zyban®) and varenicline (Champix®). The Program also covers 2 non-prescription nicotine replacement therapy products: Thrive® nicotine chewing gum and Habitrol® nicotine patches. The Program is open to all B.C. residents who wish to stop smoking or using tobacco products. For more information on the Program, please visit the B.C. Smoking Cessation Programwebsite or call HealthLink BC at 8-1-1 to begin the program.

For general information on quitting smoking and an overview of smoking cessation aids, see HealthLinkBC File #30c Quitting Smoking. This HealthLinkBC File also provides information on support services available from Quit Now Services.


Generic Name Brand Name
varenicline Champix

How It Works

Varenicline is a pill you take that acts on sites in the brain affected by nicotine. Like nicotine medicines, varenicline helps with craving and withdrawal symptoms . But it also blocks the effects of nicotine from tobacco. If you start smoking again while taking varenicline, the medicine lowers the sense of satisfaction you get from smoking, improving the chances that you will quit.

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Varenicline does not contain nicotine and does not help you quit smoking in the same way that nicotine replacement therapy does.

You start taking varenicline about a week before you quit smoking, and you take it for a total of 12 to 24 weeks.

Why It Is Used

Doctors prescribe varenicline to help adults quit smoking. It is not available as anover-the-counter medicine.

Varenicline has not been studied in children under age 18 and is not recommended to help them quit smoking.

How Well It Works

Varenicline doubles or triples the chances of quitting smoking. 1 And it may work better than other treatments for quitting smoking.

Side Effects

Some of the common side effects include:

  • Nausea and, in rare cases, vomiting.
  • Vivid, strange, or unusual dreams.
  • Constipation.
  • Feeling sleepy.

Stop taking this medicine and call your doctor right away if you or someone around you notices that you:

  • Feel anxious or nervous.
  • Feel upset, tense, or edgy.
  • Feel depressed or angry.
  • Feel different, with unusual emotions.
  • Behave in ways that are not typical for you.
  • Have suicidal thoughts or actions.
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Before you take varenicline, be sure to tell your doctor if you have ever had a mental illness.

Warning. Health Canada and the U.S. Food and Drug Administration (FDA) warn that people who are taking varenicline (Champix) and who experience any serious orunusual changes in mood or behaviour or who feel like hurting themselves or someone else should stop taking the medicine and call a doctor right away. The FDA also warns that varenicline (Champix) may be linked with a small, increased risk of heart problems (including heart attack) in people who have heart disease.

Friends or family members who notice these changes in behaviour in someone who is taking varenicline (Champix) for smoking cessation should tell the person their concerns and advise him or her to stop taking the drug and to call a doctor right away.

Varenicline is not addictive. Tell your doctor about side effects that bother you or that do not go away.

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See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

You start taking varenicline about a week before you plan to stop smoking. You may notice that you do not get the same satisfaction from cigarettes during that week. Try not to increase your smoking to overcome this.

Tell your doctor if you:

  • Have kidney problems.
  • Are pregnant or plan to become pregnant.
  • Are breast-feeding.
  • Have ever had a mental illness such as depression  or bipolar disorder .




  1. Varenicline (Chantix) for tobacco dependence (2006). Medical Letter on Drugs and Therapeutics, 48(1241/1242): 66–68.

Last Revised: November 9, 2011

Author: Healthwise Staff

Medical Review: Adam Husney, MD – Family Medicine & Brian D. O’Brien, MD – Internal Medicine & John Hughes, MD – Psychiatry