Varenicline (Chantix) for Quitting Smoking

Discusses varenicline (Chantix), medicine that helps people quit smoking. Explains that it blocks the effect of nicotine and helps with cravings and withdrawal symptoms. Covers side effects and risks if you have depression or bipolar disorder.

Varenicline (Chantix) for Quitting Smoking


Generic Name Brand Name
varenicline Chantix

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. You can take varenicline for 12 weeks longer than other medicines for a total of 24 weeks.

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

There are three ways to quit smoking when you take varenicline. These methods are:

  • Fixed: You will stop smoking after you have taken varenicline for one week.
  • Flexible: You can pick a date to quit smoking between 8 and 35 days after you start taking varenicline.
  • Gradual: You cut your smoking in half every 4 weeks until you quit at the end of 12 weeks, or sooner.

Why It Is Used

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

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.footnote 1 And it may work
better than other medicines for quitting smoking.

Side Effects

Some of the common side effects

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

Chantix may be linked with a small increase in risk for heart problems (including heart attack). Call your doctor if you have cardiovascular disease symptoms that are new or getting worse, such as chest pain or pressure, shortness of breath, calf pain when walking, or sudden onset of weakness, numbness, or difficulty speaking.

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
  • Have suicidal thoughts or actions.

Before you take varenicline, be sure to tell your doctor if
you have ever had a mental illness.

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

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 a week or more 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 breastfeeding.
  • Have
    ever had a mental illness such as
    depression or
    bipolar disorder.

Complete the new medication information form (PDF) ( What is a PDF document? ) to help you understand this medication.



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

Other Works Consulted

  • Facts and Comparisons eAnswers (2017). Varenicline tartrate oral. Facts and Comparisons eAnswers. :// Accessed May 11, 2017.
  • Ebbert J, et al. (2015). Effect of varenicline on smoking cessation through smoking reduction: A randomized clinical trial. JAMA, 313(7): 687–694. doi: 10.1001/jama.2015.280. Accessed online April 26, 2017.


ByHealthwise StaffPrimary Medical Reviewer Adam Husney, MD – Family Medicine Kathleen Romito, MD – Family Medicine Elizabeth T. Russo, MD – Internal Medicine Specialist Medical Reviewer Michael F. Bierer, MD – Internal Medicine,

Current as ofNovember 29, 2017