Mood and Behavior Changes
Chantix can cause changes in mood, thinking, or behavior in some people.
These may include:
- Depression
- Agitation
- Irritability
- Unusual behavior
- Suicidal thoughts or actions
Tell your healthcare provider right away if you notice new or worsening mood or behavior changes.
Seek urgent medical help if you have thoughts of harming yourself.
Mental Health History
Tell your healthcare provider if you have a history of depression, anxiety, bipolar disorder, psychosis, or another mental health condition.
You may need closer monitoring while taking Chantix.
Driving and Operating Machinery
Chantix may cause dizziness, drowsiness, difficulty concentrating, or other effects that can affect alertness.
Avoid driving or operating machinery until you know how the medication affects you.
Kidney Problems
Varenicline is removed from the body mainly through the kidneys.
If you have moderate or severe kidney impairment, your dose may need to be reduced.
Tell your healthcare provider if you have kidney disease before starting Chantix.
Alcohol
Chantix may change how you respond to alcohol.
Some people have reported increased intoxication, unusual behavior, or memory problems when drinking alcohol while taking varenicline.
Consider reducing your alcohol intake until you know how Chantix affects you.
Seizures
Seizures have been reported in some people taking Chantix.
The risk may be higher if you have a history of seizures or other factors that make seizures more likely.
Tell your healthcare provider if you have ever had a seizure.
Heart Problems
Tell your healthcare provider if you have a history of heart disease, heart attack, stroke, chest pain, or other cardiovascular problems.
Seek medical attention if you develop new or worsening chest pain, severe shortness of breath, or other concerning heart symptoms.
Liver Problems
Chantix is not significantly processed by the liver, so liver disease does not usually require a dose adjustment.
However, tell your healthcare provider about any serious liver condition or other medical problem before starting treatment.
Vivid or Unusual Dreams
Vivid, unusual, or strange dreams can occur while taking Chantix.
Tell your healthcare provider if these dreams are severe, disturbing, or interfere with your sleep.
When to Seek Medical Attention
Contact your healthcare provider if you develop severe or unusual side effects.
Seek immediate medical attention for suicidal thoughts, seizures, serious allergic reactions, severe skin reactions, or other symptoms that feel life-threatening.
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