Champix (varenicline) is sold as tablets on prescription only. They do not contain nicotine. The active ingredient is varenicline tartrate.
Champix works by reducing withdrawal symptoms, and by reducing the satisfying effects of smoking. When you puff on a cigarette, nicotine travels through your lungs, into your bloodstream and to your brain. It attaches to receptors in your brain to release a brain reward chemical called dopamine. Champix attaches to the receptors instead of the nicotine, and releases a smaller amount of dopamine. This reduces withdrawal symptoms when you stop smoking, such as cravings, poor moods, poor concentration and restlessness. However, it may not stop withdrawal symptoms completely.
Champix also blocks nicotine from attaching to the receptors. So if you smoke while using varenicline, the nicotine does not have its full effect, and the cigarette may not be as enjoyable or satisfying.
How well does Champix work?
People who use Champix together with counselling are more than twice as likely to quit and stay stopped, compared to those not using quitting medications. Advice or counselling is provided by the Quitline or from your doctor, pharmacist or other trained advisor.