Antibiotic resistance – prevention

Antibiotic resistance leads to higher medical costs, longer hospital stays and, sometimes, death. Key ways to prevent antibiotic resistance are by avoiding infections, using antibiotics correctly and disposing of them safely.

What is antibiotic resistance?

Antibiotics are a group of medicines designed to treat bacterial infections. They have only been available as a treatment for a few decades. However, the misuse and overuse of antibiotics have allowed some bacteria to genetically mutate to resist these medicines. This is called antibiotic resistance.

If bacteria become resistant to antibiotics, this means the antibiotics stop working and it is a serious threat to everyone’s health. Some bacteria, or 'super bugs', are now resistant to all known antibiotics and cannot be treated easily. 

In New Zealand, antibiotic-resistant bacteria are increasing. Preventing infection, using antibiotics appropriately and disposing of them safely are key ways of fighting antibiotic resistance.

How can you prevent antimicrobial resistance?

(World Health Organization, 2021)

Avoid infection in the first place

Avoiding infections in the first place reduces the amount of antibiotics that have to be used worldwide. This reduces the chance for bacteria to develop resistance during treatment. Avoiding infections also prevents the spread of resistant bacteria. 

Simple ways to avoid infections include washing your hands and getting vaccinated.

Wash your hands

Infections can be avoided by simple measures such as washing your hands or, if that's not possible, using an alcohol-based hand gel. Wash your hands regularly and especially after using the toilet and before preparing food. Many strains of bacteria are spread by person-to-person contact and can survive on surfaces like doorknobs, desktops and benchtops. Read more about handwashing.

Get vaccinated

Vaccination is a way of preventing infectious diseases such as mumps, measles, chickenpox and whooping cough. Vaccination uses your body’s natural defence mechanism (your immune system) to build resistance to specific infections.

If you have been vaccinated and you come into contact with that disease, your immune system will respond to prevent you developing the disease. Vaccination can lessen the chances of you getting sick, which in turn reduces the likelihood that you will be prescribed antibiotics or other medications. Read more about immunisation.

Use antibiotics correctly

Only use antibiotics for an infection caused by bacteria

Antibiotics are effective against infections caused by bacteria. They don't work against infections caused by viruses such as the common cold and the flu. Having green or yellow-coloured mucous, phlegm or snot isn’t always a sign of a bacterial infection. Read more about snot and sputum. 

Symptoms such as cough, sore throat, earache and fever don't always mean that you have a bacterial infection. While some people with these symptoms will need antibiotics, most people won’t because the infection can be caused by viruses. In those cases, the infection will get better without antibiotics.

Only use antibiotics when prescribed by a doctor

Your doctor will assess your condition and use their clinical judgment to prescribe a particular antibiotic if they think it is needed. Before prescribing, they will consider your symptoms, exposure to infection and test results, other medicines you are taking and any allergies you may have.

Never share antibiotics with others

Antibiotics you are prescribed may not work for your family/whānau member, friend or neighbour’s illness. They might not need antibiotics at all. If they do, they might need a different dose or type of antibiotic. They may have an allergy or another condition or be taking other medicines that mean your antibiotics are not suitable. 

Using antibiotics when they are not needed, or taking the wrong antibiotic, exposes bacteria to antibiotics unnecessarily, which encourages antibiotic resistance.

Don't use antibiotics left over from a previous prescription

The type, dose and amount of antibiotics left over may not be enough to fight a new infection. This creates more opportunity for resistant bacteria to develop and multiply. Different infections may need different treatments, even though you might have similar symptoms.

If your condition is caused by bacteria, to treat it effectively you need to get the right antibiotic, at the right dose, for the right period of time. Using antibiotics when they are not needed or taking the wrong antibiotic exposes bacteria to antibiotics unnecessarily, which encourages antibiotic resistance.

Another thing to keep in mind is that just like food, antibiotics go off. Keeping leftover antibiotics may lead you to take expired medicines, which means they may not work when you need them or may make you feel more ill. Liquid antibiotics often need to be kept in the fridge and expire quickly; other antibiotics may not be labelled with a specific expiry date. 

Should you finish a course of antibiotics?

Often you will feel better before your course of antibiotics is finished. More studies are showing that shorter courses of antibiotics are just as effective as longer courses. However, treatment guidelines are being updated with this new information, so your prescriber will take this into account when they decide your treatment.

For some infections it is important to take antibiotics for a while after you feel better to make sure the infection is gone, so it is always best to complete your antibiotics as advised the prescriber. If in doubt, talk to your prescriber.

Dispose of antibiotics correctly

Take unused antibiotics to the pharmacy for safe disposal

If you have leftover antibiotics from previous use, dispose of them correctly by returning them to your pharmacy for safe disposal.

Don't put them down the toilet or sink. There is a risk that antibiotics poured down the sink or flushed down the toilet may pass through treatment systems and enter rivers, lakes and even drinking water supplies. In homes that use septic tanks, antibiotics flushed down the toilet could leach into the ground and seep into ground water.

Antibiotics that get into the environment may drive bacteria to become more resistant. Appropriate disposal of antibiotics by the pharmacy minimises this risk. Unused medicines taken to pharmacies are disposed of by specialist waste disposal companies.

Learn more

Your family and antibiotics – what you need to know Pharmac, NZ
Antimicrobial resistance
Ministry of Health, NZ
Drug infections are hard to treat (MaoriRoyal Society, Te Aparangi, NZ  
Keeping antibiotics effective, with your help Canterbury District Health Board, NZ
Antibiotics can help, but they cal\n also harm Canterbury District Health Board, NZ
Your health is very important to us Canterbury District Health Board, NZ 


  1. Antimicrobial resistance – implications for New Zealanders Royal Society, Te Aparangi, NZ
  2. Antibiotic awareness week – a time to reflect on how we prescribe BPAC, NZ, 2017
  3. Antibiotic resistance questions and answers Centers for Disease Control and Prevention, US
  4. Keeping antibiotics working Pharmaceutical Society, NZ 
Credits: Sandra Ponen, Pharmacist. Reviewed By: Angela Lambie, Pharmacist, Auckland Last reviewed: 27 Jul 2020