Chantix Side Effects
Headaches, changes in taste, and nausea are some of the most commonly reported side effects with Chantix. Rare side effects, occurring in less than 1 percent of people, include psoriasis, vision problems, and high cholesterol. Potentially serious side effects that may require immediate medical attention include signs of an allergic reaction, difficulty breathing, and high blood pressure.
As with any medicine, side effects are possible with Chantix™ (varenicline tartrate); however, not everyone who takes the drug will have problems. In fact, most people tolerate it quite well. If side effects do occur, in most cases, they are minor and either require no treatment or can easily be treated by you or your healthcare provider.
(This article covers many, but not all, of the possible side effects with Chantix. Your healthcare provider can discuss a more complete list of Chantix side effects with you.)
Chantix has been studied thoroughly in clinical trials. In these studies, the side effects that occur in a group of people taking the drug are documented and are then compared to side effects that occur in another group of people not taking the medicine. This way, it is possible to see what side effects occur, how often they appear, and how they compare to the group not taking the medicine.
In these studies, the most common side effects of Chantix included:
- Nausea -- in up to 30 percent of people
- Insomnia -- up to 19 percent (see Chantix and Insomnia)
- Headaches -- up to 19 percent
- Abnormal dreams -- up to 13 percent
- Gas -- up to 9 percent
- Changes in taste -- up to 8 percent
- Constipation -- up to 8 percent.
Other common side effects, occurring in 1 to 7 percent of people, included:
- Abdominal pain (stomach pain)
- Indigestion or heartburn
- Gastroesophageal reflux disease (also known as GERD or acid reflux)
- Dry mouth (see Chantix and Dry Mouth)
- Fatigue or weakness
- Runny nose
- Increased or decreased appetite.
Weight gain was also a frequently reported side effect, although the exact percentage was not reported (see Chantix and Weight Gain). Also, up to 3 percent of people experienced sleeping problems and irritability when stopping Chantix abruptly (see Chantix Withdrawal).