Varenicline icon

Varenicline is a pill you take twice a day. You start taking it at least one week before you quit, gradually increasing the dose. It does not contain nicotine, so it works differently than the nicotine replacement medicines.


  • Simple to use so may be easier to stick with it.
  • Your chance of successful quitting with a single medicine is best with varenicline.
  • Varenicline gets in the way of nicotine in the brain so you don’t enjoy nicotine as much if you use a cigarette.
  • Can gradually reduce your smoking, since you start taking it before quitting.


  • Need to take it with food or a full glass of water to help avoid nausea.
  • May cost more if you have to pay for it yourself.
  • Requires a prescription.

Possible Side Effects (talk to your doctor or other healthcare provider about what you can do):

  • Nausea or vomiting at full dose (take with food or a glass of water. If persists, talk to your doctor about lowering the dose).
  • Sleep disturbances such as difficulty sleeping and vivid dreams (talk to your doctor about lowering your evening dose).
  • Constipation or flatulence (talk to your healthcare provider about diet changes or over-the-counter medicines you can take).
  • Changes in your mood or behavior (rare – see precautions)

Varenicline Precautions (If any of these apply to you, talk to your doctor or other healthcare provider before starting to take varenicline.):

  • Severe kidney problems (dose may need to be lowered).
  • Could be pregnant or are breastfeeding.
  • Less than 18 years old.

In addition, if you decide to take varenicline and experience hostility, agitation, depression, suicidal thoughts, or changes in how you act that you don’t think are due to quitting smoking, you should stop taking the medicine and talk to your doctor right away.

More precautions and general information are available about varenicline.

The quit-smoking medicines talked about on this website are approved by the FDA for adults to use to quit cigarettes. If you are pregnant, breastfeeding, or younger than 18, you should not use these medicines without talking to your doctor. If you use tobacco products other than cigarettes (like cigars, chew, snuff, hookah, or e-cigarettes), talk to your doctor or other healthcare provider or call the quitline (1-800-QUIT-NOW) to get help with quitting. All the ways to use medicines presented here are reviewed in Smoking Cessation: A Report of the Surgeon General (Chapter 6) [PDF-1.8 MB]. Some of the ways have not been evaluated or approved by the FDA.