Medication for quitting smoking

Photo of a packet of pills

Taking medication to help you quit smoking can increase the chances of success. The possible side effects include temporary sleep problems and nausea.

Two medications to help people quit smoking tobacco are commonly used in Germany: bupropion (trade name: Zyban) and varenicline (EU: Champix, U.S.: Chantix). Cytisine (Asmoken) is also approved for this use. They are prescription-only, so they have to be prescribed by a doctor. Varenicline is not currently available.

There are many studies on the effectiveness of bupropion and varenicline. In the studies, the researchers looked at whether the participants still smoked, or had started smoking again, after 6 to 12 months.

There may be individual medical reasons related to why you should or shouldn’t use these medications. It is best to discuss this with your doctor. And it’s important to let your doctor know about any other medications you are taking. That helps to avoid possible interactions between the medications.

These medications may make you feel tired and affect your ability to drive because they influence chemical messengers in your brain. So it’s a good idea to wait before operating heavy machinery or driving a car to see how you react to them.

How is bupropion (Zyban) used?

The drug bupropion was originally developed for the treatment of depression. Because it was also found to help relieve nicotine withdrawal symptoms, it was approved as an aid to quit smoking, under the trade name “Zyban.” It is taken once or twice a day in the form of a tablet, and doesn’t have to be taken with meals. One tablet contains 150 mg of bupropion.

You start the treatment before trying to quit smoking: The first tablet is taken 1 to 2 weeks before the day on which you want to quit. You then carry on taking the tablets for seven weeks. The total cost of one round of treatment with Zyban is about 150 euros. The exact cost will depend on what dose you use, for example.

How effective is bupropion?

Researchers from the systematically analyzed studies on the use of bupropion to quit smoking. The results show that bupropion helps about 7 out of 100 people to successfully quit smoking.

Illustration: How effectively bupropion helps people to quit smoking – as described in the information

Some studies looked into whether taking 300 mg of bupropion per day is more effective than taking 150 mg of bupropion per day. They showed that the higher dose didn’t have any benefit.

What side effects does bupropion have?

The possible side effects of bupropion include sleep problems, mouth dryness and nausea. About 9 out of 100 participants experienced sleep problems. Mouth dryness and nausea were less common. There is also a very small risk of serious side effects such as seizures. These side effects occurred in considerably less than 1 out of 100 participants.

How is varenicline (EU: Champix, U.S.: Chantix) used?

Another medication that’s available for people who would like to quit smoking is called varenicline (trade name: Champix in the EU, Chantix in the U.S.). It has two effects:

  • It relieves nicotine withdrawal symptoms, and
  • it makes smoking less pleasurable.

Treatment with varenicline is also started one to two weeks before you try to quit smoking. The dose is then gradually increased. You take:

  • one 0.5 mg tablet per day on the first 3 days of treatment,
  • two 0.5 mg tablets per day on days 4 to 7 of treatment, and
  • two 1 mg tablets per day from the second week of treatment onwards. You also stop smoking during the second week of treatment.

Varenicline tablets are taken in the morning and evening with a glass of water, not necessarily with meals. The treatment lasts twelve weeks in total.

How effective is varenicline?

Varenicline can effectively help you quit smoking. Studies show that it helps about 13 out of 100 people to stop smoking tobacco.

Illustration: How effectively varenicline helps people to quit smoking – as described in the information

What side effects does varenicline have?

Varenicline caused nausea in about 19 out of 100 people in the studies. But the nausea was often only mild and went away again during the course of the treatment. About 5 out of 100 people had sleep problems and/or strange dreams.

The aim of gradually increasing the dose at the beginning of the treatment is to prevent side effects like nausea. People who still don’t tolerate varenicline well can reduce the dose by half (two 0.5 mg tablets per day). If you has advanced kidney failure, you shouldn’t take more than 1 mg per day.

Is varenicline safe?

Serious side effects of varenicline are very rare to non-existent. Several studies involving more than 10,000 participants didn’t show any risks. But a small risk cannot be ruled out completely. So it’s a good idea for people who have chronic diseases to point out their health problems to the doctor before using varenicline.

Are other medications available?

The drug cytisine is also approved for use in quitting smoking. It increases the likelihood of successfully quitting as well. There are fewer studies on cytisine than there are on the other approved medications, though.

Some other medications, including some antidepressants and plant-based medicines made from St. John’s wort, are also considered as treatments for quitting smoking. But they are not well studied for this purpose. Studies done so far don’t show that they can help.

Batra A, Kiefer F, Andreas S et al. S3-Leitlinie „Rauchen und Tabakabhängigkeit: Screening, Diagnostik und Behandlung“. AWMF-Registernr.: 076-006. 2021.

Benowitz NL, Pipe A, West R et al. Cardiovascular Safety of Varenicline, Bupropion, and Nicotine Patch in Smokers: A Randomized Clinical Trial. JAMA Intern Med 2018; 178(5): 622-631.

Cahill K, Lindson-Hawley N, Thomas KH et al. Nicotine receptor partial agonists for smoking cessation. Cochrane Database Syst Rev 2016; (5): CD006103.

Howes S, Hartmann-Boyce J, Livingstone-Banks J et al. Antidepressants for smoking cessation. Cochrane Database Syst Rev 2020; (4): CD000031.

Sterling LH, Windle SB, Filion KB et al. Varenicline and Adverse Cardiovascular Events: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Am Heart Assoc 2016; 5(2): e002849.

Thomas KH, Martin RM, Knipe DW et al. Risk of neuropsychiatric adverse events associated with varenicline: systematic review and meta-analysis. BMJ 2015; 350: h1109.

IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

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Updated on September 7, 2022

Next planned update: 2025


Institute for Quality and Efficiency in Health Care (IQWiG, Germany)

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