Antibiotics - what you should know

You are encouraged to talk to your health care providers about the antibiotics you are prescribed. They can help you understand why these medicines are appropriate for you in treatment or prevention of infection.

It is important to take antibiotic medicines as instructed

Usually antibiotics are prescribed to be taken as a course of treatment. Unless instructed otherwise, it is advisable to take your antibiotics for the number of days specified by the doctor.If you have left-over tablets or capsules, return them to your local pharmacy.

Never give left-over antibiotics to a person for whom antibiotics have not been prescribed.

What to expect while taking antibiotic medicines

If you are admitted to hospital you may be given an antibiotic in the form of an injection, via a drip, or as a tablet or syrup. At the time of prescribing, your doctor will discuss your individual needs and prescribe accordingly.

Side effects

All medicines, including antibiotics, may have possible side effects. When antibiotics are necessary, the benefits far outweigh the risks, but when they are not needed, the risk is unnecessary.

Ask your doctor or pharmacist about the possible side effects of your medicine. You should also ask if there are any medicines you should not take with your antibiotic.

For more information on antibiotic side effects see the NPS website.

Antibiotic allergies

If you have had a reaction to an antibiotic in the past, you should let your nurse, doctor or pharmacist know about it and give them as many details as you can so they can decide on the best antibiotic choice. It is important to understand that not all side effects are allergies, and it may be appropriate to try the same medicine again if it is the most suitable for your infection/condition.


Some antibiotics can affect other medicines, making them more or less effective when they are taken at the same time. This is called a drug interaction. This effect can also occur with food, drinks (including alcohol) and over-the-counter products (such as herbs and vitamins).

Your health care providers have taken your medical history into account when deciding which antibiotic to prescribe. If you have any questions or concerns, speak to your doctor or pharmacist.

Antimicrobial resistance

Sometimes, when antibiotics are used when they are not needed (for example, for a common cold or flu) or for longer than is necessary, bacteria develop ways to defend against antibiotics. When this happens an antibiotic that used to work may no longer be able to cure an infection. This is called ‘antibiotic resistance’.

Doctors will only prescribe antibiotics when they are genuinely needed to minimise antibiotic resistance and ensure that antibiotics remain effective for the whole community.

Further information

For further information on antibiotics and antimicrobial resistance, see: