Bupropion hydrochloride (Zyban) for quitting smoking

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Bupropion hydrochloride (Zyban) for quitting smoking


Generic NameBrand Name
bupropion hydrochlorideZyban

How It Works

Bupropion is a pill you take to reduce your craving for tobacco. The way it does this is not entirely known. Bupropion does not contain nicotine and does not help you quit smoking in the same way that nicotine replacement therapy does.

Doctors also prescribe bupropion (under the brand name Wellbutrin) to treat depression. However, bupropion's ability to help people quit smoking is not related to its antidepressant action. It can help you stop smoking even if you do not have depression.

You begin taking bupropion daily, 1 to 2 weeks before you quit smoking. This builds up the level of medicine in your body. You take bupropion for 7 to 12 weeks after you stop using tobacco. You can take it for as long as 6 months to a year.

Why It Is Used

Bupropion is approved for use in people who smoke 10 or more cigarettes a day and are at least 18 years old. Doctors prescribe it to help people when they quit smoking.

You should not take bupropion if you:1

  • Are already taking other medicines that contain bupropion (such as Wellbutrin).
  • Have seizures or a medical condition that makes you prone to seizures.
  • Are taking a monoamine oxidase inhibitor (MAOI).
  • Have an eating disorder.
  • Have an alcohol use problem.

How Well It Works

Using bupropion for 7 to 9 weeks doubles the likelihood that you will still be tobacco-free 6 months after you quit.1 It works just as well as nicotine replacement therapies (NRTs).

Using bupropion along with nicotine replacement therapy (such as nicotine patches, gum, or inhaler) may increase your chances of success.

Taken as directed, bupropion reduces:

  • Craving.
  • Irritability, restlessness, anxiety.
  • Difficulty concentrating.
  • Feeling unhappy or depressed.

Side Effects

Common side effects include:2

  • Dry mouth, affecting 1 out of 10 people who use bupropion.
  • Difficulty sleeping (insomnia), affecting 35% to 40% of people. If you take a morning and evening dose, taking the evening dose in the afternoon may help with sleep problems. Take the evening dose at least 8 hours after the morning dose.

In over 70% of the people who use bupropion, the above side effects go away within about a week after they stop taking the medicine. Only about 10% of people have to stop taking bupropion because of side effects.

Less common side effects (occurring in less than 10% of people) include:

  • Dizziness.
  • Difficulty concentrating.
  • Upset stomach (nausea).
  • Anxiety.
  • Constipation.
  • Tremors.
  • Skin problems or rashes.

There is a small risk of having seizures when using bupropion. The risk increases if you have had seizures in the past before using bupropion.

Advisories. Health Canada and the U.S. Food and Drug Administration (FDA) have issued advisories on antidepressant medicines and the risk of suicide. It is not recommended that people stop using these medicines. Instead, a person taking antidepressants should be watched for warning signs of suicide. This is especially important at the beginning of treatment or when the doses are changed.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

You begin using bupropion 1 to 2 weeks before you quit smoking so that you build up the level of medicine in your body. Some people prefer this to other treatments because, it does not contain nicotine and they have something to rely on before their quit date. On the other hand, some people prefer a product they can take as needed for quick relief when craving occurs.

Like other treatments, bupropion works best when it is part of a program that includes setting a quit date; having a plan for dealing with things that make you reach for a cigarette (smoking triggers); and getting support from a doctor, counsellor, or support group.

Using bupropion along with nicotine replacement therapy (such as nicotine patches, gum, or inhaler) may work better than either therapy alone. Talk to your doctor before combining bupropion with nicotine replacement therapy.

Bupropion should not be used during pregnancy unless you and your doctor decide the benefits outweigh the risks and you are unable to quit smoking without using medicine.1 Women should not breast-feed while taking this medicine.3 Talk with your doctor about whether you can use this medicine during pregnancy.

Complete the new medication information form (PDF) (What is a PDF document?) to help you understand this medication.



  1. Talwar A, et al. (2004). Pharmacotherapy of tobacco dependence. Medical Clinics of North America, 88(6): 1528–1529.
  2. Drugs for tobacco dependence (2003). Treatment Guidelines From the Medical Letter, 1(10): 65–68.
  3. Holm KJ, Spencer CM (2000). Bupropion: A review of its use in the management of smoking cessation. Drugs, 59(4): 1007?1024.


By Healthwise Staff
Primary Medical Reviewer Kathleen Romito, MD - Family Medicine
Specialist Medical Reviewer John Hughes, MD - Psychiatry
Specialist Medical Reviewer Brian D. O'Brien, MD - Internal Medicine
Last Revised August 31, 2009

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.