Ask the doctor: The dangers of over-using antibiotics

Dr Clair Grainger

Medically reviewed by

Dr Clair Grainger

Last reviewed: 24 Feb 2019

Doctor explaining to woman holding antibiotics why there's a danger in over-prescribing them

1. Should I take antibiotics to cure my cough/cold/chest infection?

In most circumstances, no. Cold, flu and many chest infections are caused by viruses. Antibiotics treat bacterial infections which are a totally different thing. Bacteria are organisms that can live anywhere inside your body, while viruses live only inside of cells. Antibacterial medication won’t do anything to viruses because they’re hiding inside cells.

Antibiotics won't cure:

  • Colds or flu
  • Most coughs and bronchitis
  • Sore throats not caused by strep (Streptoccus bacteria)
  • Runny noses

2. What about with children, aren’t they more vulnerable?

Children are prone to colds, (mainly because their immune system hasn’t fully developed yet, and their nasal and sinus passages are smaller, making them more prone to viral infection). They may have 8 to 12 of them a year. Colds tend to clear up once they’ve run their course and shouldn’t be treated with antibiotics. Circumstances where antibiotics may be required are discussed below.

3. If I shouldn’t take antibiotics, then why does my doctor prescribe them?

Studies and surveys indicate that pressure from patients can lead to doctors prescribing antibiotics when they don’t feel these are needed. Sometimes antibiotics may be prescribed because it can be difficult to spot the difference between a viral and early bacterial infection.

4. Are there any circumstances where I should use antibiotics?

In certain circumstances a viral infection can ‘turn into’ a bacterial infection – usually because if you have congestion that lingers too long, it gets infected. This is known as a secondary infection and may require treatment with antibiotics. You will know when your cold or chest infection has turned into a secondary infection because your nasal discharge or phlegm will turn green or yellow and become thick in consistency (when it was white and watery before).

In cases like this, it can be suitable to take antibiotics to treat the bacterial infection.

Chest infections, sore throats, ear infections, and sinusitis can also be caused by bacteria rather than viruses in some instances. This could mean antibiotics are required.

Other tell-tale symptoms of a bacterial infection are:

  • Illness is persisting for longer than the expected 10 to 14 days that a virus tends to last for
  • Fever is higher than you might normally expect from a virus – higher than 38 degrees celsius
  • Fever gets worse a few days into the illness rather than improving
  • Pus/white spots on tonsils
  • Enlarged lymph nodes (this can also occur with some viral infections)
  • Ear pains lasting longer than 3 days

If you have any of the above symptoms you should see a healthcare professional face-to-face promptly for review.

5. What are the signs of severe infections or sepsis?

In certain patients a more severe infection or sepsis may develop. Patients at higher risk of severe or complicated infections or sepsis who should have a lower threshold for seeing a healthcare professional include:

  • Patients with a suppressed immune system (e.g. patients undergoing chemotherapy or suffering from illnesses such as HIV)
  • Patients with pre-existing lung conditions (e.g. asthma or COPD)
  • Patients with any chronic health conditions (e.g diabetes)
  • Pregnant patients
  • The elderly
  • Babies and young children
  • Smokers
  • Patients who are obese
  • Patients who have recently had surgery

Signs of a more severe infection or sepsis in adults may include:

  • Slurred speech or confusion
  • Extreme shivering or muscle pain
  • Passing no urine in a day
  • Breathlessness
  • Skin is mottled or discoloured or cold
  • Non blanching rash
  • Very high or very low temperature

Additional signs of a more severe infection or sepsis in children include:

  • Having a fit or convulsion
  • Lethargy or abnormal behaviour
  • Limb pains
  • Reduced feeding (babies)
  • Vomiting repeatedly (babies)
  • Not passing urine for 12 hours (babies)
  • HIgh pitched or continuous crying (babies)

If anyone is suffering from any of these symptoms help needs to be sought immediately by contacting 999.

6. Should I take it in the case of pneumonia?

Yes, pneumonia is commonly caused by bacterial infections. Pneumonia can be very dangerous if left untreated, particularly in the elderly.

Symptoms of pneumonia are:

  • Persistent cough
  • Fever
  • Difficulty or pain when breathing

Pneumonia is usually diagnosed by an x-ray. If you suspect you have it, go and see your doctor promptly for review.

7. So what should antibiotics be used for then?

You’d commonly use an antibiotic for things like:

  • Bladder infections
  • Many wound and skin infections, such as staph infections
  • Severe sinus infections
  • Some ear infections
  • Strep throat

8. What are the side effects of antibiotics?

The most common side-effects of antibiotics are: diarrhoea, nausea (feeling sick) and vomiting.

Some people may also suffer bouts of fungal infection (i.e. thrush) after using antibiotics, as they destroy some of the body’s ‘good’ bacteria that stop microorganisms like fungi from growing out of control.

And then there’s the risk of your body building up resistance to antibiotics if you continue to overuse them.

9. What’s building up resistance to antibiotics? How serious a risk is this?

Every time you take antibiotics, a certain number of bacteria will be killed but some, more resistant germs will be left behind to grow and multiply. If you repeatedly use antibiotics when you don’t need to, these drug-resistant strains will take over and antibiotics will stop working.

This is a serious risk. Antibiotics are notoriously difficult to discover, so if we run out of the ones we have then we won’t be able to treat serious illness. This is how things like MRSA spread.

10. I have already been prescribed antibiotics for my cold, should I stop taking them?

No, if you’ve started a course of antibiotics you should finish them.

11. What should I do to cure my cold?

The best way to deal with a cold is the old fashioned way: with plenty of bed rest and drinking lots of fluids. Just let your immune system do its job.

You may also want to talk to your pharmacist about any over the counter treatments you may be able to try to help with your symptoms.

Medically reviewed by:
Dr Clair Grainger

Dr Clair Grainger studied at The University of Edinburgh from 2004 to 2009. She's worked in hospitals throughout Edinburgh and London before completing her GP training in North Middlesex Hospital in 2017.

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Last reviewed: 24 Feb 2019

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