QUITTING SMOKING ∙ 3 minutes read

What is Champix and how does it work?

By Emily Cameron | Medically reviewed by Prof. Sam Shah

If you’re a smoker and you’re considering quitting, there are several tools out there that can help you kick the habit. Some smokers may choose to go cold turkey, while others may find that nicotine replacement therapy, behavioural therapy, medication, or a combination of multiple tools suits them best. In this article, we take a look at one of the most popular smoking cessation medications: Champix

What is Champix?

Champix helps to reduce the cravings and withdrawal symptoms that normally arise when giving up smoking. Varenicline is the active ingredient in Champix and is also known as “generic” Champix because it has the same mechanism of action, but is not associated with the Champix brand. 

Treatment is normally a 12-week course of tablets. During the first two weeks, you will continue to smoke while your body adjusts to the treatment before increasing the dose and then stopping smoking. Most people set their quit date within the second week of treatment.

How does Champix work?

Champix blocks the action of nicotine by preventing it from binding to specific receptors in your brain. This helps to lessen the cravings and withdrawal symptoms that often occur when you try to stop smoking.

When you inhale cigarette smoke, nicotine attaches to receptors in the brain that send signals to another part of the brain to release a chemical called dopamine. Dopamine gives a feeling of pleasure that lasts for a short period of time, which the body then wants to repeat – in turn increasing the likelihood of experiencing nicotine cravings.

Champix works by activating these receptors and blocking nicotine from attaching to them, reducing cravings as well as your enjoyment of cigarettes if you do choose to smoke while continuing with the treatment. 

How do I use Champix?

Champix takes a bit of planning to use correctly but is easy to use once you get into the routine of taking it. To take Champix:

  1. Set a smoking quit date before you take your first dose of Champix. The date you set should be in the second week of treatment (between days 8 and 14). We’d recommend writing your quit date on your box of tablets so you don’t forget it.
  2. Once you have set your quit date, take 0.5mg once daily for the first 1-3 days.
  3. Take 0.5mg twice daily on days 4-7.
  4. Take 1mg twice daily from day 8 until the end of the 12-week treatment.

Your doctor may suggest you take a different dose of Champix, especially if you are already taking certain medications. 

How effective is Champix?

Research has shown Champix to be an even more effective smoking cessation treatment than nicotine patches. One study demonstrated that more varenicline-treated patients stayed smoke-free during the last four weeks of their treatment than patients treated with nicotine patches.

Another study found that nearly five times as many varenicline-treated patients refrained from smoking than patients who were given a placebo drug over the course of a 52-week period.

What are the side effects of Champix?

Like all medications, Champix can cause side effects. We’ve put together a run-down of the most common side effects and how you can combat them.

  • Nausea: While you are taking Champix tablets, stick to simple meals, and stay away from rich or spicy food. You can also take the medication after you’ve had a meal or a snack.
  • Headaches: Don’t drink too much alcohol while you’re taking Champix, and make sure you drink plenty of fluids. You can also take an everyday painkiller like paracetamol. 
  • Difficulty sleeping: Try to take your last dose earlier in the evening, and leave a few hours before your bedtime. 
  • Feeling dizzy: After your body gets used to Champix, this side effect should subside. If you do experience dizziness, sit or lie down until you feel better and avoid alcohol as it will make the symptom worse. 

Who is Champix suitable for?

Champix is suitable for most people, however, it is not suitable for:

  • Children or adolescents.
  • Anyone allergic to varenicline.
  • Those taking cimetidine.
  • Patients with a predisposition to seizures.
  • Some patients with a history of psychiatric illness will require closer monitoring.

It is important you consult a clinician before taking Champix to ensure it is safe for you to take and doesn’t conflict with any medication you are taking.

The bottom line

Champix, also known as Chantix or varenicline, is a generally safe and effective treatment used to help with smoking cessation. Quitting smoking is tough, but with the right tools and support, it is achievable. The hardest part is deciding to quit, and although Champix isn’t a substitute for willpower, it is a powerful tool that can make all the difference in helping you to successfully go smoke-free.

Related articles:

How it works: the Quit Smoking Programme

What happens to your body when you quit smoking?

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