Site hosted by Build your free website today!


The pharmacological information on this page was taken directly from the product information
sheet that accompanies Zyban. For full, complete, and official information, contact Glaxo Wellcome.

Bupropion Hydrochloride, Sustained-Release Tablets

Zyban (Bupropion) is a new drug available by prescription to help people quit smoking. It includes a self-help manual and support from a toll-free telephone service. Bupropion is also packaged under the name Wellbutrin SR (Sustained Release). Wellbutrin is intended for use as an anti-depressant, but Zyban is intended for use as an aid to stop smoking. Although it is the same drug (Bupropion), their marketing and packaging and intended uses are kept separate. (For more information, see below.)

Dosages of 300 mg/day have been shown to be effective for stopping smoking in non-depressed persons (effectiveness on depressed persons has not yet been studied). Zyban appears to decrease a person’s urge to smoke, and it lessens withdrawal symptoms. The course of treatment can begin one week before a person’s quit date, and runs 7 to 12 weeks. It can be used with a Nicotine Patch (or Gum, or any other "Nicotine Replacement Therapy"), but may be just as effective with or without using Nicotine Replacement at the same time. This resource page first presents FAQ's [Frequently Asked Questions], then describes the Pharmacology of Zyban, studies done so far, side effects, and other important information (see below).

FAQ's [Frequently Asked Questions]

1. What is Zyban?

Zyban is a prescription medicine to help people quit smoking. Studies have shown that more than one third of people quit smoking for at least 1 month while taking ZYBAN and participating in a patient support program. For many patients, ZYBAN reduces withdrawal symptoms and the urge to smoke. ZYBAN should be used with a patient support program. It is important to participate in the behavioral program, counseling, or other support program your health care professional recommends.

2. Who should not take Zyban?

You should not take ZYBAN if you:

- have a seizure disorder (for example, epilepsy).

- are already taking WELLBUTRIN, WELLBUTRIN SR, or any other medicines that contain bupropion hydrochloride.

- have or have had an eating disorder (for example, bulimia or anorexia nervosa).

- are currently taking or have recently taken a monoamine oxidase inhibitor (MAOI).

- are allergic to bupropion.

3. Are there special concerns for women?

ZYBAN is not recommended for women who are pregnant or breast-feeding. Women should notify their doctor if they become pregnant or intend to become pregnant while taking ZYBAN.

4. How should I take Zyban?

- You should take ZYBAN as directed by your doctor. The usual recommended dosing is to take one 150 mg-tablet in the morning for the first 3 days. On the fourth day, begin taking one 150-mg tablet in the morning and one 150-mg tablet in the early evening. Doses should be taken at least 8 hours apart.

- Never take an "extra" dose of ZYBAN. If you forget to take a dose, do not take an extra tablet to "Catch up" for the dose you forgot. Wait and take your next tablet at the regular time. Do not take more tablets than your doctor prescribed. This is important so you do not increase your chance of having a seizure.

- It is important to swallow ZYBAN Tablets whole. Do not chew, divide, or crush tablets.

5. How long should I take ZYBAN?

Most people should take ZYBAN for 7 to 12 weeks. Follow your doctor’s instructions.

6. When should I stop smoking?

It takes about 1 week for ZYBAN to reach the right levels in your body to be effective. So, to maximize your chance of quitting, you should not stop smoking until you have been taking ZYBAN for 1 week. You should set a date to stop smoking during the second week you’re taking ZYBAN.

7. Can I smoke while taking Zyban?

It is not physically dangerous to smoke and use ZYBAN at the same time. However, continuing to smoke after the date you set to stop smoking will seriously reduce your chance of breaking your smoking habit.

8. Can Zyban be used at the same time as nicotine patches?

Yes, ZYBAN and nicotine patches can be used at the same time but should only be used together under the supervision of your doctor. Using ZYBAN and nicotine patches together may raise your blood pressure. Your doctor will probably want to check your blood pressure regularly to make sure that it stays within acceptable levels.

DO NOT SMOKE AT ANY TIME if you are using a nicotine patch or any other nicotine product along with ZYBAN. It is possible to get too much nicotine and have serious side effects.

9. What are possible side effects of Zyban?

Like all medicines, ZYBAN may cause side effects.

- The most common side effects include dry mouth and difficulty sleeping. These side effects are generally mild and often disappear after a few weeks. If you have difficulty sleeping, avoid taking your medicine too close to bedtime.

- The most common side effects that caused people to stop taking ZYBAN during clinical studies were shakiness and skin rash.

- Contact your doctor or health care professional if you have a rash or other troublesome side effects.

Use caution before driving a car or operating complex, hazardous machinery until you know if ZYBAN affects your ability to perform these tasks.

10. Can I drink alcohol while I am taking Zyban?

It is best to not drink alcohol at all or to drink very little while taking ZYBAN. If you drink a lot of alcohol and suddenly stop, you may increase your chance of having a seizure. Therefore, it is important to discuss your use of alcohol with your doctor before you begin taking ZYBAN.

11. Will Zyban affect other medicines I am taking?

ZYBAN may affect other medicines you are taking. It is important not to take medicines that may increase the chance for you to have a seizure. Therefore, you should make sure that your doctor knows about all medicines – prescription or over-the-counter – you are taking or plan to take.

12. Do Zyban Tablets have a characteristic odor?

ZYBAN Tablets may have a characteristic odor. If present, this odor is normal.

13. How should I store Zyban?

- Store ZYBAN at room temperature, out of direct sunlight.
- Keep ZYBAN in a tightly closed container.
- Keep ZYBAN out of the reach of children.


ZYBAN is a non-nicotine aid to smoking cessation. Initially developed and marketed as an antidepressant (WELLBUTRIN [bupropion hydrochloride] Tablets and WELLBUTRIN SR [sustained release tablets], ZYBAN is chemically unrelated to tricyclic, tetracyclic, selective serotonin re-uptake inhibitor, or other known antidepressant agents. Its structure closely resembles that of diethylpropion; it is related to phenylethylamines.

ZYBAN is a relatively weak inhibitor of the neuronal uptake of norepinephrine, serotonin, and dopamine, and does not inhibit monoamine oxidase. The mechanism by which ZYBAN enhances the ability of patients to abstain from smoking is unknown. However, it is presumed that this action is mediated by noradrenergic and/or dopaminergic mechanisms.

ZYBAN is given to a patient 150 mg/day (one tablet per day) for three days, and then the dosage is increased to 300 mg/day (2 tablets per day of 150 mg). The course of treatment, which begins ONE WEEK BEFORE THE TARGET QUIT DATE can be 8 weeks or more. It can be stopped abruptly. It can be combined with nicotine replacement therapy (see study 2, below).

ZYBAN is packaged along with self-help smoking cessation materials, called the ZYBAN Advantage Plan, which includes a "Plan to Succeed Workbook" prepared with the assistance of Michael Fiore, MD, Director of the Center for Tobacco Research and Intervention at the University of Wisconsin Medical School. Also included is access to a toll-free number. This number, 1-800-UCAN-QUIT (1-800-8226-7848 [sic.]), provides enrollment in the ZYBAN Advantage Plan (enrollment can also be accomplished by mailing in a questionnaire). This plan is personalized, and provides support and helpful tips based on information provided by the patient.


The efficacy of ZYBAN as an aid to smoking cessation was demonstrated in two placebo-controlled, double-blind trials in nondepressed chronic cigarette smokers (n=1,508 , >= 15 cigarettes per day). In these studies, ZYBAN was used in conjunction with individual smoking cessation counseling.

The first study was a dose-response trial conducted at three clinical centers. Patients in this study were treated for 7 weeks with one of three doses of ZYBAN (100, 150, or 300 mg/day) or placebo; quitting was defined as total abstinence during the last 4 weeks of treatment (weeks 4 through 7). Abstinence was determined by patient daily diaries and verified by carbon monoxide levels in expired air.

Results of this dose-response trial with ZYBAN demonstrated a dose-dependent increase in the percentage of patients able to achieve 4-week abstinence (weeks 4 through 7). Treatment with ZYBAN at both 150 and 300 mg/day was significantly more effective than placebo in helping patients achieve 4-week abstinence. In addition, treatment with ZYBAN (7 weeks at 300 mg/day) was more effective than placebo in helping patients maintain continuous abstinence through week 26 (6 months) of the study.

The second study was a comparative trial conducted at four clinical centers. Four treatments were evaluated; ZYBAN 300 mg/day, HABITROLâ (nicotine transdermal system) (NTS) 21 mg/day, combination of ZYBAN 300 mg/day plus NTS 21 mg/day, and placebo. Patients were treated for 9 weeks. Treatment with ZYBAN was initiated at 150 mg/day while the patient was still smoking and was increased after 3 days to 300 mg/day given as 150 mg twice daily. NTS 21 mg/day was added to treatment with ZYBAN after approximately 1 week when the patient reached the target quit date. During weeks 8 and 9 of the study, NTS was tapered to 14 and 7 mg/day, respectively. Quitting, defined as total abstinence during weeks 4 through 7, was determined by patient daily diaries and verified by expired air carbon monoxide levels.

In this study, patients treated with either ZYBAN or NTS achieved greater 4-week abstinence rates than patients treated with placebo. In addition, patients treated with the combination of ZYBAN and NTS achieved higher abstinence rates than patients treated with either of the individual active treatments alone, although only the comparison with NTS achieved higher abstinence rates than patients treated with either of the individual active treatments alone, although only the comparison with NTS achieved statistical significance. Both ZYBAN and NTS were more effective than placebo in helping patients maintain abstinence through week 10 of the study. The treatment combination of ZYBAN and NTS displayed the highest rates of continuous abstinence throughout the study.

Quit rates in clinical trials are influenced by the population selected. Quit rates in an un-selected population may be lower than the above rates. Treatment with ZYBAN reduced withdrawal symptoms compared to placebo.

Reductions on the following withdrawal symptoms were most pronounced: irritability, frustration, or anger; anxiety; difficulty concentrating; restlessness; and depressed mood or negative affect.

Depending on the study and the measure used, treatment with ZYBAN showed evidence of reduction craving for cigarettes or urge to smoke compared to placebo.


Side Effects reported include (but are not limited to) Insomnia, Headache, Nausea (some), Dry mouth, and Seizure.

Seizure risk increases if there is a CNS lesion, or other predisposing factors. Seizure risk also increases when ZYBAN is combined with other antidepressants. Alcohol also lowers seizure threshold.

This summary provides important information about ZYBAN. This summary cannot replace the more detailed information that you need from your doctor. If you have any questions or concerns about either ZYBAN or smoking cessation, talk to your doctor or other health care professional.

FAQ's and Pharmacological Information
Copyright 1997 Glaxo Wellcome.
Glaxo Wellcome Inc.
Research Triangle Park, NC 27709
All rights reserved.

For the official ZYBAN site sponsored by Glaxo-Wellcome, click HERE.

Email Smoking Research Program at:

BACK to: Smoking Factoids, in Rochester, NY