Skip to main content

Varenicline tablets

Editor’s note

Dr Krishna Vakharia, 9th August 2022

Varenicline (Champix®) products were discontinued in the United Kingdom and Europe in April 2022 due to impurities in the medicine. At the time of review there are no branded or generic products containing varenicline available in the UK. Varenicline may still be available in other countries. This medicine leaflet is based on medical information available in the UK at the time of writing and is left here for reference purposes. Please also refer to the manufacturer's information supplied with your medicine.

A combination of varenicline with counselling can increase your chance of successfully stopping smoking.

Start taking the tablets at least a week before your target stop date.

Tell your doctor if you develop any side-effects. The most commonly reported side-effects are feeling sick, problems sleeping, headache, and nose and throat infections.

Continue reading below

About varenicline

Type of medicine

A smoking cessation aid - a selective nicotine-receptor partial agonist

Used for

Helping people to stop smoking

Also called

Champix® (discontinued)

Available as


Nicotine is a drug that is inhaled from the tobacco in cigarettes. It gets into the bloodstream and stimulates the brain. Most regular smokers are addicted to nicotine. Even though you want to stop smoking, it can be difficult to succeed, because nicotine addiction is strong and hard to break. This is where varenicline can help.

Varenicline mimics the effect of nicotine on the body. This both reduces the urge to smoke and relieves withdrawal symptoms. It also blunts the effect of nicotine in people who give in to temptation and have a cigarette. This reduces the enjoyment of smoking.

Varenicline will not make you stop smoking. You will still need determination to succeed and to break the smoking habit. A combination of varenicline with counselling from a nurse, doctor, pharmacist, or other health professional is likely to increase your chance of successfully stopping smoking. Therefore, most doctors will only prescribe varenicline to people who really want to stop smoking as part of a stopping smoking programme.

Before taking varenicline

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking varenicline it is important that your doctor knows:

  • If you are pregnant, trying for a baby or breastfeeding.

  • If you are under 18 years of age.

  • If you have ever had a mental health problem such as depression.

  • If you have ever had a heart or blood vessel problem.

  • If you have a problem with the way your kidneys work.

  • If for any reason you are at risk of having a seizure.

  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

  • If you have ever had an allergic reaction to a medicine.

Continue reading below

How to take varenicline

  • Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about varenicline and stopping smoking. It will also provide you with a full list of the side-effects which can be associated with varenicline.

  • Take varenicline exactly as your doctor tells you to. You will be asked to set yourself a date on which to stop smoking. Your doctor will then ask you to start taking varenicline tablets at least a week before this 'quit' date. The aim is to build up the dose so that your body gets used to the medicine before your quit date.

  • Start by taking one white tablet (500 microgram) once daily for the first three days. Then on days four to seven, take one white tablet twice a day, one in the morning and one in the evening. On day eight onwards, take one light blue tablet (1 mg) twice a day. A full course of treatment lasts for 12 weeks in total. The course may be continued for a further 12 weeks if you have successfully stopped smoking but your doctor feels it will be of help to you.

  • It is not important whether you take varenicline tablets before or after food, but it is best if you try to take your doses at the same time(s) each day. This will help you to remember to take the tablets regularly. Take each dose with a glass of water - do not chew or break the tablets before you swallow.

  • If you do forget to take a dose, take it as soon as you remember unless it is nearly time for your next dose (in which case leave out the missed dose). Do not take two doses together to make up for a forgotten dose.

Getting the most from your treatment

  • Try to keep your regular appointments with your doctor or nurse. This is so that you can be given counselling and encouragement, and also so that a check can be kept on your progress.

  • Make sure that your doctor or healthcare professional knows if you are taking any other medicines. This is because stopping smoking can change the way your body breaks down certain medicines. So, as a result of quitting, the dose of some prescribed medicines may need to be adjusted.

  • After your course of treatment, your doctor may suggest that you gradually reduce the dose over a week or so, before you finally stop taking varenicline. This is because a few people have experienced problems for a short time when they have stopped taking varenicline suddenly - these have included an urge to smoke again, feeling depressed or irritable, and sleeping difficulties. Although this only occurs in a small percentage of people, reducing the dose slowly reduces the risk of it happening.

Continue reading below

Can varenicline cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with varenicline. You will find a full list in the manufacturer's information leaflet supplied with your medicine. You should tell your doctor if you develop any unwanted effects, as a reduction in dose may be an option for you. Some of the symptoms may also occur as a result of stopping smoking.

Most common varenicline side-effects

What can I do if I experience this?

Headache, other aches or pains

Drink plenty of water and ask your pharmacist to recommend a suitable painkiller. If the pains continue, let your doctor know

Feeling sick (nausea) or being sick (vomiting), stomach upset, indigestion

Keep to simple foods. Try taking the tablets after meals

Feeling sleepy or dizzy

Do not drive or use tools or machines until you feel better

Disturbed sleep, unusual dreams

Try to avoid taking your last dose near to bedtime

Dry mouth

Try chewing sugar-free gum or sucking sugar-free sweets

Nose and throat infections, change in appetite, increased weight, changes in the way things taste, feeling short of breath, cough, itchy rash

If troublesome, speak with your doctor

Important: if you become agitated or depressed, or if you start having thoughts about harming yourself, you must stop taking varenicline and let your doctor know straightaway. These symptoms can occasionally occur as a side-effect of treatment, and they can also occur as a result of nicotine withdrawal. If you experience any other symptoms which you think may be due to the tablets, speak with your doctor or pharmacist for further advice.

How to store varenicline

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

Important information about all medicines

Important information about all medicines

If you buy any medicines, always check with a pharmacist that they are safe to take with your other medicines.

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.

This medicine is for you. Do not give it to others, even if their condition appears to be the same as yours.

If you are having any medical treatment, tell the person carrying out the treatment which medicines you are taking.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about your medicines, ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

symptom checker

Feeling unwell?

Assess your symptoms online for free