How Do Antibiotics Kill Bacteria?

Our body is exposed to many illness causing bacteria every single day. But surely that does not iterate to the fact that we fall ill each day, because our own fighting soldiers in the body; i.e. the immune system is capable enough to back them off.

However, this fact would be quite partially stated that our immune system at all times can fight off all illness causing germs and bacteria, because there are certain possible times when it cannot be completely effective in its job of defeating all these, and might need the help of antibiotics.


Understanding Antibiotics

Anti-biotics are a certain kind of medicine which the doctors may prescribe to treat illnesses caused by bacteria specifically.  Diseases such as pneumonia and tuberculosis being some of the most serious ones have been cured in patients with anti-biotics.

There can be different kinds of anti-biotic medicines that is possible. These are essentially produced from naturally occurring fungi and bacteria, which when ejected inside the body can fight and kill the harm causing bacteria present over there.

History Of Antibiotics

The first anti-biotic drug that was ever discovered was called Penicillin found in the year 1928. However what is more interesting to note that such a phenomenal discovery in the history of medical science was simply a result of an accident.

It is believed that Alexander Fleming, the scientist who has been credited for this remarkable discovery had in reality mistakenly left some bacteria he was testing uncovered in his laboratory as he went out. Upon his return he witnessed that these bacteria were killed by the fungus that grew on them!


The first ever anti-biotic to have been produced, it is one of the most preferred form of anti-biotic medicine in heavy use till date.  It works by weakening gradually the cell membranes of the disease causing bacteria, in a way that it simply bursts open within itself, thereby killing it instantly.

Doctors prescribe this penicillin anti-biotic to patients in forms of oral pills or liquids.

Functioning Of An Antibiotics

Anti-biotics may work in two ways in the body. One may be simply by killing off the bacteria, the other being that it would stop the bacteria from multiplying. Assists the natural immune system of the body to fight off the illness easily.

However, there are certain barriers to the functioning of an anti-biotic. While they may be rendered completely ineffective against viruses, but there are some situations as well when the bacteria itself stop becoming responsive to the action of the anti-biotic and modifies itself to grow immune to the effectiveness of the anti-biotic.

These types of bacteria, called ‘Superbugs’ are where anti-biotics become incapable to cure.

Fun Facts

  • Though anti-biotics are a good way to treat a bacteria-caused illness, however it is advised that sometimes it may be good for the body to treat it naturally without any medicinal help!
  • Anti-biotics are only effective against bacteria, not virus causing illnesses.

Related questions

Some related questions to this topic.

  1. Soaps claim to kill of bacteria present in your hands. Does that mean that they too have anti-biotic properties?
  2. Why cant flu be treated with anti-biotics? What is required to treat such illnesses?
  3. Can anti-biotics prove to be harmful to the body?

Objective Quiz

Here are some questions you’d like to answer to test your knowledge.

Anti-biotics cant kill:

  • Superbugs
  • Viruses
  • Both
  • None

First ever anti-biotic to be created was:

  • Crocin
  • Paracetamol
  • Penicillin

Anti-biotics work by:

  • Slowly killing the bacteria
  • Breaking the cell wall
  • Both
  • None

Serious diseases that can be cured by anti-biotics:

  • Tuberculosis
  • Cancer
  • Diabetes
  • Fever

Anti-biotics are made of:

  • Naturally occurring fungi and bacteria cells
  • DNA of the bacteria causing illness
  • None of the above

True Or False

  1. Alexander Fleming discovered the first ever anti-biotic. (True/False)
  2.  Viral diseases can be cured by anti-biotics. (True/False)
  3. Excessive anti-biotic usage makes our body immune to it, thereby making it ineffective. (True/False)
  4. Anti-biotics may cause some side effects. (True/False)
  5. Penicillin was found in the year 1976. (True/False)

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