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HealthInfo Canterbury

Why don't I need antibiotics?

no antibioticsInfections are caused by different types of bugs or germs, and each one is treated differently.

Antibiotics work against bacteria, which are one type of germ. But most infections are caused by germs called viruses.

Viruses can affect many parts of your body. They are the main cause of colds and sinusitis, middle ear infections, sore throats, chest infections like bronchitis, flu, and diarrhoea and vomiting (gastroenteritis).

Bacteria are a different type of germ. They can cause infections in many different parts of your body, such as urinary tract infections, pneumonia and skin infections.

Antibiotics do not work against viruses, they only work against bacteria.

There are some medicines that work against a few viruses. They are called antivirals. But most viruses do not have medicines that work against them.

Your doctor will work out whether your infection is caused by a bacteria or a virus and whether antibiotics may work for you.

Your immune system

Your immune system attacks and kills all types of germs and defends you against infections. It can fight off most types of viruses and bacteria, but it can take several days or weeks to do this.

While your immune system is fighting a virus you might still feel unwell. This can be frustrating. You want to feel better, but antibiotics won't help you feel better. In fact, the side effects may make you feel worse.

While you wait for your immune system to get rid of a viral infection it is important to rest, drink plenty of fluids (so you don't get dehydrated), and eat a healthy diet. Ask your doctor of pharmacist how to deal with symptoms such as a fever, blocked nose, or sore throat. Paracetamol or ibuprofen might help if you have a fever or pain.

What's wrong with taking antibiotics?

You might wonder why you can't give antibiotics a try, just in case they help to make you feel better. There are good reasons why you shouldn't take antibiotics unless you really need them.

Antibiotics might cause unwanted side effects, like diarrhoea, vomiting, and thrush. Rarely, people can get very serious side effects, such as liver problems or life-threatening allergies.

As well, they also kill good bacteria inside your body. This can lead to other health problems and cause antibiotic resistance.

What is antibiotic resistance?

Bacteria can change when they come into contact with antibiotics – they can change so much that the antibiotics no longer affect them. This is called antibiotic resistance.

Antibiotic resistance bacteria (sometimes called superbugs) can lead to some serious infections that are very hard to treat or that we can't treat at all (often called superbugs). This is important for your own health and for the health of the people around you.

We need antibiotics to treat serious infections caused by bacteria, like meningitis and pneumonia. So, it's really important to only take them when you need them.

The Canterbury DHB pamphlet Keeping antibiotics effective, with your help talks about when, and when not, to use antibiotics. It also discusses the global threat of antibiotic-resistant bacteria.


Written by HealthInfo clinical advisers. Last reviewed November 2017.


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Review key: HIANT-307383