Skip to main content

Bupropion for quitting smoking


If you want to stop smoking, taking bupropion (trade name Zyban®) roughly doubles your chance of success.

Continue reading below

What is bupropion?

Bupropion (Zyban®) is a medicine that was first developed to treat depression. It was found that it helped smokers to stop smoking. It seems to relieve the withdrawal symptoms that you experience when you stop smoking (such as craving, feeling anxious, restlessness, headaches, irritability, hunger, difficulty concentrating, or just feeling awful).

How does bupropion work?

It is not clear how it works. It alters the level of some chemicals in the brain (neurotransmitters).

Continue reading below

Smoking and nicotine addiction

Most people who quit smoking have tried three or four times to do so before they succeed. This is because smoking, or more specifically nicotine in cigarette smoke, is highly addictive. You start to get withdrawal symptoms only a few hours after smoking a cigarette. Bupropion (Zyban®) can help by reducing these withdrawal symptoms.

To read more about how addictive smoking can be and to find out how addicted you are, see the separate leaflet called Quit Smoking (Smoking Cessation).

How effective is bupropion for quitting smoking?

Taking bupropion does increase the chance of quitting smoking. Various studies have looked at this issue. The studies compared bupropion to a similar dummy (placebo) tablet in people who were keen to stop smoking.

The results from the studies showed that, on average, about 19 in 100 people who took bupropion stopped smoking successfully. This compared to about 10 in 100 who took the dummy tablet.

In other words, about twice the number of smokers who take bupropion stop smoking compared to those who don't take bupropion. About 1 in 5 smokers who want to stop will do it with the help of bupropion.

Continue reading below

How to take bupropion

  • You need a prescription to obtain bupropion - you cannot buy it at pharmacies.

  • Start by taking one tablet (150 mg) each day for six days. Then increase to one tablet twice a day, at least eight hours apart. Do not take more than one tablet at any one time, and not more than two tablets in a day. (If you are elderly or if you have certain liver or kidney diseases, your dose of bupropion may be different - your doctor will advise.)

  • Set a target date to stop smoking one to two weeks after starting treatment. This allows bupropion to build up in your body before you stop completely.

  • You should continue the tablets for a further seven weeks. (So, this is eight weeks in total, which is two packs of tablets.)

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

Is bupropion safe?

Most people take bupropion without any problem. Read the packet leaflet for a full list of possible side-effects and cautions. The most common are a dry mouth (which occurs in about 1 in 10 users) and some difficulty in sleeping (which occurs in about 1 in 3 users). Less common but more serious possible side-effects include the following:


If this occurs you should not drive and you should not operate machinery.

A seizure (fit or convulsion)

This occurs in about 1 in 1,000 people who take bupropion. Therefore, although this is uncommon, it can be serious, particularly if it occurs when you are operating machinery or driving.

The risk of a seizure is increased if you have a history of certain medical conditions, or if you take certain medicines (listed below). Therefore, bupropion is not suitable for all people who wish to stop smoking (see below) as it sometimes increases the risk of having a seizure.

High blood pressure

Blood pressure sometimes goes up in people who take bupropion. You should have a baseline blood pressure reading done before you start treatment and it should be monitored from time to time.

Bupropion weight loss

Some people experience weight loss when taking bupropion. However, the effect on body weight is variable and your weight may stay the same or even increase when taking bupropion.

Bupropion overdose

The main risk of overdose is a seizure. Death can occur but is rare.

How to report bupropion side-effects

If you think you have had a side-effect to one of your medicines you can report this on the Yellow Card Scheme. You can do this online at

Who should not take bupropion?

You should not take bupropion if you:

Also, the dose may need to be reduced if you have some medical conditions or if you take certain medicines. Tell your doctor or pharmacist if you:

  • Have ever had a serious head injury.

  • Have diabetes that is treated with insulin or medicines.

  • Drink a lot of alcohol.

  • Have a liver or kidney disease.

Bupropion combined with certain other medicines can increase the risk of having a seizure. Therefore, whilst you are taking bupropion, tell your doctor or pharmacist if you are prescribed or buy any new medicine.

Also, tell a doctor or pharmacist if you are taking any of the following medicines so they can be alert for possible drug interactions:

  • Antimalarial medicines (for example, chloroquine, proguanil).

  • Antihistamines.

  • Medicines to treat depression eg, Selective Serotonin Reuptake Inhibitors (SSRIs) or monoamine oxidase inhibitors (MAOIs), or medication for Attention Deficit Hyperactivity Disorder (ADHD) may increase the risk of serotonin syndrome.

  • Theophylline, which is a medicine used to treat chest conditions.

  • Steroids - taken as tablets or injections.

  • Antibiotics.

  • Tramadol, which is a strong painkiller.

  • Slimming medicines or other stimulant medicines.

If you are unable to take bupropion, there are other ways that you can get help to quit. See the separate leaflet called Quit Smoking (Smoking Cessation).

Further reading and references

  • Wu J, Sin DD; Improved patient outcome with smoking cessation: when is it too late? Int J Chron Obstruct Pulmon Dis. 2011;6:259-67. doi: 10.2147/COPD.S10771. Epub 2011 May 2.
  • Tobacco: preventing uptake, promoting quitting and treating dependence; NICE guideline (2021 - last updated January 2023)
  • Yan T, Goldman RD; Bupropion for smoking cessation in adolescents. Can Fam Physician. 2021 Oct;67(10):743-745. doi: 10.46747/cfp.6710743.
  • Smoking cessation; NICE CKS, April 2023 (UK access only)
  • Evins AE, Benowitz NL, West R, et al; Neuropsychiatric Safety and Efficacy of Varenicline, Bupropion, and Nicotine Patch in Smokers With Psychotic, Anxiety, and Mood Disorders in the EAGLES Trial. J Clin Psychopharmacol. 2019 Mar/Apr;39(2):108-116. doi: 10.1097/JCP.0000000000001015.
  • Bupropion; Drugs and Lactation Database (LactMed®) [Internet]. Bethesda (MD): National Institute of Child Health and Human Development; 2006–. Bupropion. 2023 Jan 15.
  • Hajizadeh A, Howes S, Theodoulou A, et al; Antidepressants for smoking cessation. Cochrane Database Syst Rev. 2023 May 24;5(5):CD000031. doi: 10.1002/14651858.CD000031.pub6.

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