Table of contents
Medically reviewed by
Dr Daniel Atkinson
GP Clinical lead
on November 07, 2022.
Meet Daniel  
Was this article useful?

Stop smoking tablets: Zyban side effects

Zyban can be prescribed to people to aid them in their journey to quitting smoking. Zyban comes as a tablet to be taken orally, once a day (upping to twice a day after the first two weeks for those under 65) for around seven to nine weeks. Alongside ongoing motivational support, Zyban can help you successfully stop smoking in the long term.

Before we start a quick mention that all medications can cause side effects, both prescription and over the counter treatments. That’s why it’s vital to always be aware of all potential side effects before you start taking your chosen treatment.

Read the patient information leaflet provided with your prescription and consult your prescriber if you have any concerns regarding the side effects listed on this brochure.

What are the side effects of Zyban?

Whilst taking Zyban to quit smoking comes with countless benefits to your health, those interested in this treatment should be aware of all the potential risks involved. This includes both the more common, generic bupropion side effects and the incredibly rare, more serious ones.

The most common Zyban side effect is difficulty sleeping. Other common side effects include headaches, nausea, dizziness, constipation, weight loss, dry mouth, fast heartbeat, and a sore throat. These side effects should improve over the first week or two of taking the medication.

Less common side effects of taking bupropion-based medications include anxiety, tremors, stomach pain, irritability, depression, lack of concentration, headaches and dizziness, nausea and vomiting, constipation, dry mouth, fever, sweating, skin irritation, and itching.

Rare side effects include tinnitus (ringing in the ears), confusion, hot flushes, problems with vision, high blood pressure, raised heart rate, loss of appetite, loss of strength, and chest pain.

Incredibly rare side effects of bupropion include coordination issues, palpitations, feeling faint, anaphylaxis (allergic reaction), loss of memory, increased urination, increased or decreased skin sensitivity, and hallucinations. Also, commonly listed as an extremely rare side effect is seizures.

Due to the lack of data, it is currently unknown if Zyban can cause harm to fetuses. However, it is not advised to take bupropion (the active ingredient in Zyban) during pregnancy.

Zyban: serious side effects

Like any prescription drug, there can be serious side effects of taking this medication, such as those listed above. Whilst these are extremely rare, we encourage you to discuss any concerns regarding these more severe side effects with your prescriber in order to reduce any anxieties you might be experiencing.

One of the most serious side effects listed is seizures, however, these have only ever occurred in individuals taking incredibly high doses of Zyban or who have mixed Zyban with other substances. One such study analysing a potential link between bupropion and seizures showed that they occured in less than 0.25% of users, supporting the drug’s safety as a stop smoking treatment.

In addition, like any type of medication, there is a slight chance that some people will experience an allergic reaction. A bupropion allergic reaction may cause a rash, swelling of the mouth, tongue, or throat, and trouble breathing.

People who quit smoking may experience weight gain as a side effect. This can happen because smoking both speeds up your metabolism and suppresses your appetite.

But does bupropion make you gain weight?

No. In fact, some people find the opposite occurs. Bupropion weight loss is considered a side effect of taking Zyban, even though it is not directly linked. However, studies have shown that individuals using bupropion as an antidepressant lost weight while those taking other antidepressants gained weight.

Whilst smoking can exacerbate your appetite for other vices, such as drinking alcohol, taking bupropion whilst drinking alcohol is not advised.

Mixing Zyban with alcoholic beverages can increase the risk of the more rare side effects. Some risks of bupropion interactions with alcohol include seizures, nausea, vomiting, and anxiety.

Like many other drugs used to treat depression, there is a risk of hair loss with bupropion.

However, the good news is that this hair loss is not particularly common, nor is it permanent. We hope that reduces any bupropion hair loss concerns.

Insomnia is one of the most commonly observed side effects of taking Zyban. However, this side effect can be easily counteracted by reducing your dosage of Zyban or avoiding nighttime doses. You should speak to your doctor if you think that Zyban is affecting your sleep.

High blood pressure is one of the rarer side effects of taking bupropion that you should keep an eye out for. If you are taking Zyban as a smoking cessation treatment, your doctor may wish to monitor your blood pressure regularly.

There has only ever been a single case recorded in which a bupropion user experienced sexual dysfunction, and studies into the drug concluded that this was an atypical and anomalous side effect.

Moreover, bupropion is often prescribed to treat sexual dysfunction-induced depression and anxiety.

Bupropion interactions

When you’re considering taking Zyban to help quit smoking, make sure you disclose any other medication or treatments you are taking or have recently taken with your prescriber. Whilst Zyban is a safe drug, proven to aid those wishing to live a life free of cigarettes, there are serious risks when mixing bupropion with other medications.

Not only can this alter the effectiveness of Zyban or your other medications, but it can also significantly increase the chances of you experiencing side effects.

The risk of harmful side effects occurring is particularly high if you’re taking Zyban with certain antidepressants, antipsychotics, and treatments for daytime sleepiness or narcolepsy. Less severe but still concerning side effects may occur if you take Zyban with certain antibiotics, antiemetics (anti-nausea drugs), hormone therapy drugs, steroids and diabetes medicine.

What to do if you experience Zyban side effects

If you are experiencing any side effects whilst taking Zyban, you need to inform the prescribing doctor so that they may advise you on what steps you should take.

Any side effects, but particularly the more severe ones, should be reported via the Yellow Card Scheme, a system designed to collect and monitor any side effects or adverse reactions to medications and treatments.

It could be that Zyban is not the smoking cessation treatment for you, but this shouldn’t dishearten you in your quest to stop smoking. There are alternative treatments available that can help you curb your smoking habit safely and successfully so you can live a healthier, smoke-free life.

Reference Popover #ref1
Reference Popover #ref2
Reference Popover #ref3
Reference Popover #ref4
This page was medically reviewed by Dr Daniel Atkinson, GP Clinical lead on November 07, 2022. Next review due on November 07, 2024.

How we source info:

When we present you with stats, data, opinion or a consensus, we’ll tell you where this came from. And we’ll only present data as clinically reliable if it’s come from a reputable source, such as a state or government-funded health body, a peer-reviewed medical journal, or a recognized analytics or data body. Read more in our editorial policy.

What did you like about it?

What didn't you like about it?

Suggest a treatment

If there’s a particular treatment or condition you’re looking for, tell us and we’ll look into it for you.

We may email you about the problem, but you can opt out of these communications any time you like.

Tell us about a problem

I accept the terms of use.
We may email you about the problem, but you can opt out of these communications any time you like.

Ask or suggest something.

Submit your question here, or tell us if you’ve found an issue on our site.

We may email you about your query, but you can opt out of these communications any time you like.

Our average rating based on 19746 reviews.


Get the latest health news and articles, sent to your inbox.

By clicking 'Subscribe now' you're agreeing to our Terms.

You’re signed up to our newsletter. Keep an eye on your inbox for our latest update.

We’ll get back to you very soon. We aim to respond to all queries in one working day.