Side Effects of Varenicline
The most common side effects of varenicline seen in clinical trials include nausea, headache, and insomnia. Rare side effects include cataracts, migraines, and diarrhea. There are also some varenicline side effects that, while occurring infrequently, are potentially serious and should be reported to a healthcare provider immediately, including difficulty breathing, high blood pressure, and extreme nausea or vomiting.
As with any medicine, side effects are possible with varenicline tartrate (Chantix™); however, not everyone who takes the medication will experience side effects. 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 varenicline. Your healthcare provider can discuss a more complete list of varenicline side effects with you.)
Some side effects with varenicline, while occurring infrequently, are potentially serious and should be reported immediately to your healthcare provider. These include but are not limited to:
- Extreme nausea or vomiting
- Difficulty breathing
- Suicidal behavior
- Psychotic, aggressive, or strange behavior
- Signs of a stroke, such as:
- Vision or speech changes
- Weakness or numbness in an arm or leg
- Severe headache
- Chest pain or heaviness, which may be signs of a heart attack
- High blood pressure (hypertension)
- Signs of an allergic reaction, including unexplained rash, hives, itching, and unexplained swelling.