Bupropion to quit smoking

Sounds like bue-PROE-pee-on

Bupropion is used to help adults stop smoking. Find out how to take it safely and possible side effects. Bupropion is also called Zyban.

Type of medicine Also called
  • Medicine to stop smoking
  • Zyban®

What is bupropion?

Bupropion is used to help adults stop smoking. It is usually used when nicotine replacement therapy (NRT) has not been effective. 

  • Bupropion can help balance chemicals in your brain to reduce the withdrawal symptoms that happen while you give up smoking. It works by changing the brain's response to nicotine and makes smoking less pleasurable and also reduces craving.
  • Bupropion is only available from your pharmacy so you’ll usually need to see your doctor or contact an stop smoking service to get it.

Note: Bupropion is also used to treat depression. Read more about bupropion for depression

What are the benefits of bupropion?

Taking bupropion increases your chances of quitting smoking. It approximately doubles the chances of giving up smoking long-term. It doesn't contain nicotine, which is important to some people. Bupropion can delay weight gain after quitting for some people.


  • The effects of bupropion are not immediate. It is best to start bupropion 1 to 2 weeks before you plan to stop smoking. This allows bupropion to build up in your body before you stop smoking completely.
  • In Aotearoa New Zealand bupropion is available as tablets (150 mg).
  • Take one tablet once a day for three days, then take one tablet two times a day, for at least seven weeks.
  • There should be at least eight hours between doses.
  • If you are elderly or have certain liver or kidney diseases, the dose may be different — your doctor will advise you about this.

How to take bupropion

  • Swallow the tablets whole with a glass of water. Do not crush or chew the tablets because if you do that it releases all the medicine at once and can increase your chance of side effects.
  • Timing: You can take bupropion with or without food. Bupropion can cause sleep problems, so don't take it just before bedtime. Try taking it early in the evening. If you are taking a twice daily dose, take it at least eight hours or more after your morning dose. 
  • Avoid or limit drinking alcohol while you are taking bupropion. Drinking alcohol while taking bupropion may increase the risk for mood changes.
  • Missed dose: If you forget to take your dose, take it as soon as you remember that day. But, if it is nearly time for your next dose, just take the next dose at the right time. Do not take double the dose. Remember there should be at least eight hours between doses.

Things to consider when taking bupropion

Taking other medicines and supplements: Bupropion can interact with some medications, herbal supplements and rongoā Māori, so check with your doctor or pharmacist before starting bupropion and before starting any new products.

Possible side effects of bupropion

Like all medicines, bupropion can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.

Increased risk of seizures 

Bupropion can increase the risk of seizures. This happens in about one in 1,000 people who take bupropion. Although this is rare, it can be serious, especially if it occurs when you are driving or operating machinery. The risk of a seizure is increased if you:

  • take more than two tablets per day
  • have had a head injury
  • drink a lot of alcohol
  • are taking medicines that can cause fits, such as antipsychotics, antidepressants, antimalarials, tramadol, theophylline, corticosteroids and some antihistamines 
  • have diabetes and are being treated with insulin or medicines.

Other side effects

Side effects What should I do?
  • Dry mouth
  • Sore throat
  • Feeling sick (nausea)
  • Headache
  • These are quite common when you first start taking bupropion and usually go away with time.
  • Tell your doctor if you are finding them troublesome.
  • Read about treatments for dry mouth. 
  • Loss of appetite — not wanting to eat because food tastes different
  • Try eating or drinking small amounts but frequent meals
  • Avoid eating in an environment with strong smells.
  • Sleep problems, difficulty falling asleep 
  • This is common when you first start taking bupropion but goes away with time. 
  • Avoid taking your dose at bedtime. Take it early in the evening, or if you are taking a twice a day dose, take it eight hours or more after your morning dose.
  • Feeling sleepy, drowsy or tired during the day
  • Poor concentration
  • Be careful when driving or using tools until you know how this medicine affects you.
  • You will have a greater risk of falls and injuries, especially if you are elderly. Tell your doctor if you are concerned.
  • Do not drink alcohol.
  • Changes in behaviours or thinking
  • Mood swings
  • Feeling anxious
  • Depression (new or worsening)
  • Thoughts of suicide
  • These are rare but serious side effects.
  • Tell your doctor immediately or ring Healthline 0800 611 116.
  • Signs of a severe allergic reaction such skin rash, itching, swelling of the lips, face and mouth or difficulty breathing
  • Stop using bupropion.
  • Tell your doctor immediately or ring Healthline 0800 611 116.
Did you know that you can report a side effect to a medicine to CARM (Centre for Adverse Reactions Monitoring)? Report a side effect to a product

Learn More

Zyban Medsafe Consumer Information Sheet


  1. Bupropion hydrochloride NZ Formulary, NZ 2022
  2. Zyban Medsafe, NZ
Credits: Health Navigator Pharmacists. Reviewed By: Sandra Ponen, Pharmacist Last reviewed: 22 May 2022