From the Guidelines
Champix (varenicline) can cause several side effects, but the most recent and highest quality study suggests that common adverse effects include nausea, insomnia, abnormal dreams, headache, and fatigue, with no statistically significant increase in neuropsychiatric adverse events or cardiovascular adverse events 1.
Common Side Effects
- Nausea, which affects about 30% of users
- Headaches
- Difficulty sleeping
- Abnormal dreams
- Constipation
- Changes in taste
- Increased appetite
- Dry mouth
- Fatigue
Serious Side Effects
- Mood changes
- Depression
- Suicidal thoughts
- Allergic reactions
- Cardiovascular events like heart attack or stroke The medication works by binding to nicotine receptors in the brain, both blocking nicotine's effects and stimulating the release of dopamine to reduce cravings and withdrawal symptoms.
Recommendations
- Patients should report any concerning side effects to their healthcare provider immediately, especially mood changes or suicidal thoughts, as dosage adjustments or discontinuation may be necessary.
- The benefits of varenicline for smoking cessation outweigh the risks, and it is considered safe for use in patients with cancer who smoke, with a favorable risk/benefit ratio 1.
- However, varenicline should be avoided in patients with brain metastases who have a history or elevated risk of seizure 1.
From the FDA Drug Label
What are the possible side effects of varenicline tablets? Serious side effects of varenicline tablets may include: Seizures. New or worse heart or blood vessel (cardiovascular) problems, mostly in people, who already have cardiovascular problems. Sleepwalking can happen with varenicline tablets, and can sometimes lead to behavior that is harmful to you or other people, or to property. Allergic reactions can happen with varenicline tablets. Serious skin reactions, including rash, swelling, redness, and peeling of the skin. The most common side effects of varenicline tablets include: nausea sleep problems (trouble sleeping or vivid, unusual, or strange dreams) constipation gas vomiting
Common side effects of Champix (varenicline) include:
- Nausea
- Sleep problems
- Constipation
- Gas
- Vomiting Serious side effects of Champix (varenicline) may include:
- Seizures
- New or worse heart or blood vessel problems
- Sleepwalking
- Allergic reactions
- Serious skin reactions 2
From the Research
Common Side Effects of Champix
- Nausea was the single most frequently reported adverse event in varenicline clinical trials, with an incidence that was sex-related and increased with varenicline exposure 3
Comparison with Other Smoking Cessation Therapies
- Varenicline appeared to attenuate the urge to smoke, negative affect withdrawal symptoms and the reinforcing effects of smoking, making it a valuable new agent for use as an aid to smoking cessation treatment 4
- A direct comparison of varenicline with bupropion has shown that varenicline is as least as good as and probably more effective than bupropion for smoking cessation 5
Special Considerations
- For smokers with major depressive disorder (MDD), varenicline plus counseling may be the best pharmacological option for the treatment of smoking given its greater efficacy effect size and similar risk of neuropsychiatric adverse events 6
General Information
- Varenicline (Champix) is a partial agonist of nicotinic receptors, and is currently accepted for sale for smoking cessation 7