Stop smoking - Medical information

Quit rate doubled with Champix

Clinical studies have shown that taking Champix can more than double the rate of success in stopping smoking compared with dummy (placebo) tablets. About 22 in 100 people who took Champix stopped smoking permanently compared to about 8 in 100 who took the dummy (placebo) tablets.

How Champix works

Champix replaces nicotine in the body and blocks its effects. This means whilst a person takes Champix there is less craving for cigarettes and smoking is less pleasurable.

Champix dose

Champix tablets are taken twice-daily usually for 12 or 24 weeks.

Start with a Champix Starter Pack to build the dose up slowly over the first 7 days.

Start 1-2 weeks before the target stop smoking date, initially one 0.5mg once daily for 3 days, increased to one 0.5mg tablet twice daily for 4 days, then one 1mg tablet twice daily for 11 weeks (reduce to one 0.5mg twice daily if not tolerated). The complete course is for 12 weeks. It can be repeated for a further 12 weeks if there are still significant withdrawal symptoms. A course of Champix can also be repeated if a person restarts smoking.

Side effects of Champix

Not everyone experiences side effects. The most common reported side effects are nausea, nose or throat inflammation, difficulty sleeping, abnormal dreams, and headache. Some people experience depression and even suicidal thoughts whilst taking Champix, in which case treatment should be stopped and a doctor consulted.


People with a history of psychiatric disorders or active depression should not take Champix.

Some people relapse or experience insomnia and depression for a few days when they stop taking Champix (this can be avoided by tapering the dose down before stopping completely). Some people may even feel suicidal after stopping Champix The evidence is unclear as to whether this is a definite effect of Champix but if you are affected seek medical help.

Support services

As with all medication taken to help stop smoking, Champix works best if there is other support at the same time.

GP surgeries, pharmacies, and local councils may provide access to a variety of stop smoking support services. There is also the following:

  • NHS England — the free Smokefree National Helpline on 0300 1231044 or online NHS stop smoking services help you quit
  • NHS Better Health - Quit smoking. This offers support via a smartphone app, email programme, text messages, and a Facebook page.
  • NHS Scotland - the free Smokeline on 0800 848484, or online NHS inform - Stopping smoking.
  • NHS Wales — the free Help Me Quit Wales Helpline on 0800 0852219.
  • NHS Northern Ireland: Public Health Agency — Stop smoking.
  • ASH (Action on Smoking and Health).
  • QUIT, a national charity which provides telephone support.
  • Stop smoking smartphone apps.