A stop-smoking medicine
Bupropion
A prescription tablet that helps people stop smoking by reducing cravings and withdrawal symptoms.
What is Bupropion?
Bupropion (Zyban) is a prescription tablet used to help people stop smoking. It reduces cravings and withdrawal symptoms and is started while you are still smoking, with a quit date set in the first couple of weeks. It can lower the seizure threshold, so it is not used in people with epilepsy or eating disorders.
Education and reference only. This is a plain-language guide to Bupropion — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Bupropion, sold as Zyban for stopping smoking, is a prescription tablet that helps reduce nicotine cravings and withdrawal symptoms. It is started while you are still smoking, with a planned quit date in the first couple of weeks, and used alongside support and willpower. (The same active ingredient is used as an antidepressant in some countries, but in the UK it is licensed here for smoking cessation.)
How it works
Bupropion acts on brain chemicals — dopamine and noradrenaline — that are involved in the reward and craving linked to nicotine. By adjusting these, it dampens the urge to smoke and eases the unpleasant symptoms of nicotine withdrawal. This makes it easier to get through the first weeks of quitting without relapsing.
Company & origin
Originated / developed by: GlaxoSmithKline (originator of Zyban).
Originally an antidepressant, later licensed in the UK as a stop-smoking aid.
Practical use
How to take Bupropion
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Start it while you are still smoking, and set your quit date for the first couple of weeks of treatment.
- Swallow the tablets whole with water; do not crush or chew them, as this can increase the risk of side effects.
- Use it alongside stop-smoking support, such as an UK health service service, for the best chance of success.
- Report any agitation, low mood or unusual thoughts, and tell your prescriber about all your other medicines.
- If you miss a dose, skip it and take the next one at the usual time — do not take two together, and leave a good gap between doses.
Weighing it up
Advantages & disadvantages of Bupropion
Advantages
- Reduces cravings and withdrawal symptoms to improve your chances of quitting.
- An option for people who would prefer a tablet to nicotine replacement.
- Most effective when combined with behavioural stop-smoking support.
Disadvantages
- Lowers the seizure threshold, so it cannot be used by people with epilepsy or eating disorders.
- Interacts with many other medicines, which limits who can take it.
- Can cause insomnia, dry mouth and, less often, mood changes.
Practical use
Good to know
It is started a week or two before your quit date while you are still smoking, then continued for a couple of months. It works best combined with behavioural support, such as an UK health service stop-smoking service. Importantly, it slightly lowers the seizure threshold, so it is not used in people with epilepsy, a history of seizures, or eating disorders, and it interacts with many medicines. Mood changes can occur, so any unusual thoughts or low mood should be reported.
Who should not take it / use with caution
- People with epilepsy or any history of seizures, as it lowers the seizure threshold.
- People with a current or past eating disorder (such as bulimia or anorexia), or who are withdrawing from alcohol or sedatives.
- People taking an MAOI antidepressant, and it is avoided in pregnancy and breastfeeding.
Monitoring
- Mood and behaviour, including any unusual thoughts, particularly in the early weeks.
- Blood pressure, especially if you have raised blood pressure or take other relevant medicines.
- Progress with quitting smoking and any side effects at follow-up.
Side effects
- Dry mouth, difficulty sleeping, headache and nausea are common.
- Dizziness, constipation, shakiness and a skin rash can occur.
- Less commonly, low mood, agitation or seizures — stop and seek advice if you have a fit, severe rash or worsening mood.
Key interactions
- It must not be combined with MAOI antidepressants, and care is needed with other antidepressants and medicines that also lower the seizure threshold.
- It can change the levels of several medicines (including some heart, antipsychotic and antidepressant drugs), so the prescriber checks your list.
- Alcohol should be limited, and tell your pharmacist about everything you take, including over-the-counter products.
Available as: Tablets (modified-release).
Answers
Bupropion: frequently asked questions
How does bupropion help me stop smoking?
It acts on brain chemicals involved in nicotine craving, reducing the urge to smoke and easing withdrawal symptoms so it is easier to quit.
Do I stop smoking before I start it?
No — you start bupropion while you are still smoking and set a quit date for the first couple of weeks, so the medicine has time to build up.
Why can't people with epilepsy take it?
Bupropion slightly lowers the seizure threshold, which makes a fit more likely. For that reason it is not used in people with epilepsy, a history of seizures, or eating disorders.
Is bupropion the same as Zyban?
Yes. Bupropion is the active-ingredient name and Zyban is the brand name licensed in the UK as a stop-smoking aid.
Can I use nicotine patches with it?
Combining bupropion with nicotine replacement is sometimes done but needs prescriber advice, partly because of effects on blood pressure. Check before using both together.
The wider class
About Smoking-cessation aids
Bupropion belongs to the smoking-cessation aids class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF: Bupropion hydrochloride.
- NICE CKS: Stop smoking treatments.
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