What are the side effects of Chantix?

The most common side effects, found in clinical trials, were nausea, sleep problems, constipation, gas, and vomiting. Chantix can cause changes in behavior and mood in some people. They may become hostile, agitated, depressed, or have suicidal thoughts or actions. Some people already had these symptoms; however, some people developed them while on Chantix or when stopping the drug.

Chantix can also cause a serious skin reaction, which could be life threatening. Skin reactions can include rash, swelling, redness, and peeling of the skin. Allergic reactions occur in some people and can also be life threatening. Symptoms are swelling of the face, mouth, and throat. This can cause trouble breathing. There may be other side effects not mentioned here. If you have any of these serious side effects, seek immediate medical attention.

Nina Evans
Chantix (varenicline) can have both serious and mild side effects. The serious side effects include mood changes (including suicidal thoughts in some people), skin rashes and allergic reactions. Tell your doctor if you have any changes in mood. Call 911 if you have an allergic reaction to Chantix.

Less serious side effects include nausea, constipation, gas, vomiting, heartburn and a bad taste in your mouth. You may also find that you’re either less hungry or hungrier than usual, have trouble falling or staying asleep, feel drowsy during the day, get headaches, or have unusual dreams or nightmares.
Most side effects of Chantix (varenicline), such as nausea, sleep problems, constipation, gas and vomiting, are minimal and resolve on their own. Tell your doctor if these persist or become bothersome.
Call your doctor if you experience other, more serious side effects including coughing, wheezing, seizures, difficulty breathing, shortness of breath or hyperventilation.
Some side effects can affect your mood and cause feelings of anxiety, anger, sadness, panic or depression. Call 911 for immediate medical attention if you have hallucinations, restlessness, agitation, suicidal thoughts or signs of an allergic reaction such as difficulty breathing, swelling of the face, mouth, lips or tongue, or chest pain.
Call 1-800-FDA-1088 to report any side effects of Chantix to the Food and Drug Administration (FDA).

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.