Varenicline (Champix) for quitting smoking

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This Medicine Update is for people who are taking, or are thinking about taking, varenicline.

This document has been updated since its original release. [Details]


Varenicline is a medicine to help people stop smoking. It works by making smoking less enjoyable and reducing cravings. You must be motivated to stop smoking and follow a counselling program to be prescribed varenicline through the Pharmaceutical Benefits Scheme (PBS).

You should start taking varenicline 1 to 2 weeks before your intended quit date. A course of treatment is 12 weeks, but this can be extended for a further 12 weeks to increase your chances of quitting long term.

If you fail to quit smoking, a second course of treatment of up to 24 weeks can be started 6 months after commencing the first course.

Be aware that varenicline is not suitable for everyone. People with a mental health problem (such as depression, schizophrenia or bipolar disorder) or a serious medical condition (like epilepsy or cardiovascular disease) should speak to their doctor about other options if they want to quit smoking using varenicline.

Varenicline is quite new compared with other treatments for quitting, so we don’t know as much about its less common side effects compared with other medicines.


What varenicline is

The active ingredient of this medicine is varenicline (pronounced VA-ren-i-kleen). It is also known by the brand name Champix.

Varenicline is a tablet to help you quit smoking. It does this by blocking the effects of nicotine.

What varenicline is for

Varenicline helps smokers quit. It’s used together with a counselling program, like the one offered by Quitline (137 848).

If you smoke, you are at higher risk of lung disease (like emphysema and lung cancer), heart attack and stroke. Smoking is bad for you — and for the people around you.

Who can take varenicline

Varenicline is available through the Pharmaceutical Benefits Scheme (PBS) if:

  • you follow a counselling program for quitting smoking over the full course of treatment
  • you are not taking other PBS-subsidised quit-smoking treatments at the same time
  • 6 months have passed since you started a course of bupropion (Prexaton, Zyban SR) — another quit-smoking treatment — or started your last course of varenicline.

Varenicline may not be suitable for everyone.

There are other quit-smoking options that may be more appropriate if you:

  • have depression, schizophrenia or bipolar disorder (see Important side effects of varenicline to consider)
  • have a serious medical condition (for example, epilepsy, cardiovascular disease or a serious lung problem called chronic obstructive pulmonary disease).

We don’t have information about the safety of varenicline in people who drink more than the recommended limit of alcohol or who use illegal drugs like marijuana.

Tell your doctor if you have kidney disease. You may still be able to take varenicline, but your doctor will need to adjust the dose.

How to take varenicline

You start taking varenicline 1–2 weeks before you intend to stop smoking (your quit date). The dose starts low and then increases slowly over the first week:

  • Days 1–3, take one white tablet (0.5 milligrams of varenicline) once a day.
  • Days 4–7, take one white tablet (0.5 milligrams of varenicline) twice daily — one in the morning and one in the evening.
  • From day 8 until the end of treatment, take one light blue tablet (1 milligram of varenicline) twice daily — one in the morning and one in the evening.

The first prescription of varenicline is for 4 weeks of treatment, but you will need to visit your doctor 2–3 weeks after starting treatment for a second prescription for the next 8 weeks. This is also an opportunity to get further support and advice.

A full course of varenicline can be 12 weeks or 24 weeks

Some people will successfully quit after a 12-week course, but your doctor may recommend a further 12 weeks of treatment (24 weeks in total) to increase your chance of quitting in the long term.

If you fail to quit after 12 or 24 weeks of varenicline treatment, provided 6 months have passed since your last varenicline treatment, you may receive a further 12 or 24 weeks of subsidised treatment.

Take the tablets with food and a glass of water

This can help to reduce nausea. Nausea affects about one in three people taking varenicline, but it usually settles with time.

Tell your doctor if nausea is troubling you, or if it is stopping you from taking your medication — you may be able to adjust the dose.

What does varenicline do?

Varenicline works by blocking the effects of nicotine.

This reduces the enjoyment of smoking when you start taking varenicline during the 1–2 week period before your quit date.

It also reduces cravings and withdrawal symptoms after you have quit.

Important side effects of varenicline to consider

Nausea, difficulty sleeping, strange dreams, headache, and stomach or bowel problems are common side effects of varenicline.

Watch for changes in mood or behaviour

It is difficult to tell the difference between varenicline’s side effects and withdrawal symptoms from smoking. These symptoms include irritability, depression and problems with sleeping — and they can also happen when you stop taking varenicline at the end of your treatment.

Some people have become depressed, anxious, agitated or even aggressive when stopping smoking.

Talk to your doctor as soon as possible if you — or people around you like family and friends — notice a change in your mood or behaviour.

If you have a mental health problem, such as depression, bipolar disorder or schizophrenia, you should discuss this with your doctor when thinking about varenicline.

Ask your health professional about the possible side effects of this medicine before you take it. Always tell them about any changes to your condition if you're taking a new medicine.

To report possible side effects call the NPS Adverse Medicine Events (AME) line on 1300 134 237 from anywhere in Australia (Monday–Friday, 9am–5pm AEST).

People with questions about their medicines or seeking general information about side effects can call the NPS Medicines Line on 1300 633 424 (Monday–Friday, 9am–5pm AEST).

Small possible increase in cardiovascular risk

In some studies, more people who took varenicline experienced a cardiovascular event — such as a heart attack — than those who took a placebo (dummy pill). It’s difficult to tell if varenicline caused these events or if they would have occurred anyway.

While the chance that varenicline may cause a heart attack appears to be small, if you experience chest pain, breathing problems, or pain in your legs when you are taking varenicline, see a doctor immediately.

Bear in mind that smoking increases the risk of heart disease or stroke — while people who quit smoking halve their risk of experiencing a heart attack 1 year after quitting.

If you have heart problems (cardiovascular disease) already, ask your doctor about your options for quitting.

Skin reactions are very rare but can be serious

Stop taking varenicline and see a doctor as soon as possible at the first sign of rash or red blisters, or swelling around your face, mouth or neck.

Wait before driving or using machinery

Varenicline can cause drowsiness. Wait to see how varenicline affects you before driving or operating machinery.

For a more complete list of possible side effects for Champix (varenicline), see the consumer medicine information (CMI) leaflet available on our Medicines search page.

What else you should know about varenicline

Using nicotine replacement therapy at the same time as varenicline can cause some side effects like nausea, headache and dizziness — or it can make them worse. It’s not yet known if the combination of varenicline and bupropion is safe to use.

So the best approach is to avoid using other quit-smoking medicines at the same time as varenicline.

Other medicines available for quitting smoking

In Australia, two other types of medicine are available to help people quit smoking.

Nicotine replacement therapy (sometimes called NRT) is safe for most people, and doctors and pharmacists know a great deal about using it. It’s often the first medicine tried to help people quit smoking. It is also suitable for people with mental health problems.

Nicotine replacement therapy works by reducing cigarette cravings. It comes in several different forms including lozenges, mini-lozenges or micro-tabs, inhalers, chewing gum, and patches. There are several brands available (for example, Chemists’ Own Nicotine, Nicabate CQ, Nicorette and QuitX). Talk to your pharmacist about the different types available and which best suits you.

The side effects — like dizziness, headache and nausea — are usually short-lived and minor. Different forms can have different side effects. For example, the chewing gum may cause stomach upset, and the patch can cause skin irritation.

You can get nicotine patches through the PBS if you have a prescription.

Bupropion is a tablet that works differently to varenicline. It is about as effective as nicotine replacement therapy. When you first start taking bupropion (brand name Prexaton or Zyban SR), you may get some mild side effects like headache, dry mouth, upset stomach and problems with sleeping. But these are usually short-lived.

Bupropion has some important side effects and interactions with other medicines that make it unsuitable for some people. Seizures (fits) are a rare side effect. The risk of having a seizure is higher in people who:

  • have had a seizure before (epilepsy)
  • take other medicines that increase the risk of having a seizure
  • have diabetes
  • have previously had a head injury
  • drink too much alcohol.

Talk to your doctor about all of the options for quitting or call the Quitline on 137 848.

How to decide between varenicline and other medicines

Remember that benefits and side effects differ between medicines and from person to person.

Personal preference is an important factor when choosing between different quitting options. You may prefer to wear a patch than take a tablet, or you may want to avoid a particular side effect. Some people may be willing to put up with a side effect if the medicine is working well for them. Think about what matters most to you, and discuss your preferences with your doctor.

Is varenicline more effective than other options?

Using varenicline increases the chances of quitting smoking long term. When considering information from clinical trials, varenicline performed better than nicotine replacement therapy or bupropion. In comparison to placebo, varenicline nearly tripled the chance of quitting.

Consider side effects when choosing

Comparing the side effects can also help you decide between varenicline and other options. For example, because varenicline can affect mood and behaviour it’s unlikely to be suitable for people with a mental health problem (see Important side effects of varenicline to consider).

What does varenicline cost?

Cost to you

If you get varenicline through the Pharmaceutical Benefits Scheme (PBS), the Australian Government pays most of the cost and you will pay only a part, called the co-payment.If you are not eligible to get varenicline through the PBS, you will need to pay the full price for a prescription.

Other ways to stop smoking

While medicines play an important role in helping some people quit, most people do it without medicines.

Non-medicine approaches include:

  • going cold turkey
  • gradually cutting down, then quitting
  • counselling.

Making up your mind

Different methods work for different people, but the most important first step is deciding to quit. That’s the key — you have to want to stop smoking. The next step is planning how to do it.

Getting support

The Quitline (137 848) or your doctor can help you increase your chance of success and learn from any past quit attempts. Also ask your friends and family for support.

Cutting down

If you are not confident about quitting immediately, you can try to gradually reduce smoking, while using nicotine replacement therapy, with the aim of quitting in the future.


Counselling can help, whether it is in a group or one to one. Quitline (137 848) offers free telephone counselling for smokers who want to quit.

It’s worth it!

Quitting at any time helps — the health of people who quit starts to improve within days. It often takes more than one attempt to be successful, even with all the best support and medicines. If the first attempt doesn’t work, try again. It’s worth it!

Where to find more information

You can find more information in the consumer medicine information (CMI). This will tell you:

  • who should not use the medicine
  • which other medicines should be avoided
  • how to take the medicine
  • most of the possible side effects
  • the ingredients.

You can get the CMI leaflet for Champix from:

Information over the phone

NPS works with healthdirect Australia to provide the Medicines Line phone service for consumers.

To get more information about any medicine call 1300 MEDICINE (1300 633 424). This service is available from anywhere in Australia, Monday to Friday, 9am to 5pm AEST excluding NSW public holidays.

To report a side effect

Call the NPS Adverse Medicine Events (AME) Line on 1300 134 237, Monday to Friday, 9am to 5pm AEST excluding public holidays.

The AME Line is a service where you can report possible side effects of your medicine and contribute to national medicine safety efforts. Information on medicine-related side effects is passed on to the Therapeutic Goods Administration (TGA) for assessment, but your personal details will remain confidential and your privacy maintained.

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Revision history

Updated November 2014 to reflect changes to the PBS listing.

First release: August 2011.