Antibiotic (Patient Advice)


Cork Emergency Departments


What Are Antibiotics?

Antibiotics are medicines that can stop some infections and save lives. When they are not used the right way, antibiotics can cause more harm than good. Your health can be safeguarded by ensuring that you do not abuse antibiotics.

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Will Antibiotics Work Against Cold or the Flu?

No. Antibiotics only work against infections caused by bacteria. They do not work at all against infections caused by viruses. Viruses cause the flu, colds and most coughs and sore throats.

What is "Bacterial Resistance?"

Usually antibiotics kill bacteria or stop them from growing but some bacteria have grown so strong that antibiotics do not work against them. These stronger bacteria (or super bugs) are called "resistant" because they resist antibiotic treatment. Resistant bacteria develop when antibiotics are used too often or are taken incorrectly (i.e. not in accordance with the instructions issued with the prescription). Resistant bacteria can sometimes be treated with more powerful antibiotics (often intravenously - through a drip, in hospital). A small number of bacteria have become multiply resistant such that they are untreatable.

What can I Do to Help Myself and My Family?

Do not expect antibiotics to cure every illness. Do not seek antibiotic prescriptions for colds or the flu. If antibiotics are prescribed, ensure that you take the complete course as prescribed by the doctor, do not take partial courses of antibiotics, and do not store stocks of antibiotic at home to use without the recommendation of a medical practitioner.

How do I Know When I Need Antibiotics?

The answer depends on what is causing your infection. The following are some basic guidelines;

Colds and flu.

These illnesses are caused by viruses. They cannot be cured by antibiotics.

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Cough or Bronchitis.

These illnesses are almost always caused by viruses. However, if you have a lung condition such as asthma, chronic obstructive pulmonary disease or emphysema, your infection may actually be caused by bacteria. Your doctor may decide to try treatment with an antibiotic, after clinical examination and/or investigation.

Sore throats.

Most sore throats are caused by viruses and do not require antibiotics. So called "strep" throat is caused by a bacteria which requires treatment with an antibiotic. Often throat swabs will be taken to determine the presence of the streptococcus bacterium.

Ear Infections.

There are several types of ear infections. Sometimes antibiotics are needed to treat an ear infection and these can be given either by mouth or by drops into the ear depending on the nature and location of the infection.

Sinus Infection.

Antibiotics are only required for severe sinus infections or for infections that are continuing for a prolonged period of time. The presence of a yellow or green mucus from the nose is not an indication that antibiotic prescription is required.

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Children's Colds and Runny Noses.

A runny nose usually starts as a child's cold is starting to get better. When the cold virus first infects the nose and sinuses, the nose starts making a lot of clear mucus. This mucus helps wash the virus out of the nose and sinuses.

After 2-3 days, as the body fights back, the mucus changes to a white or yellow colour. As the bacteria that usually live in the nose grow back, they change to mucus to a greenish colour. This is normal. It does not mean that your child has an infection that needs to be treated with antibiotics.

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Please contactyour family doctor for further information or advice about particular cases.


If you are concerned, please contact the Emergency Department you first attended:

Mercy Injury Unit, Gurranabraher (021)4926900

LIU Mallow(022)58506

LIU Bantry(027)52900


Dr Íomhar O' Sullivan 07/04/2007. Last review Dr ÍOS 17/06/21 .