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What are Antibiotics and How Do They Work?

Antibiotics have been in the news a lot recently. If it isn’t continued warnings about their overuse, it’s stories about how researchers are finding new ones in the most unlikely of places. They have been one of the medical marvels of our age, turning once life-threatening conditions into minor issues that clear up after a week or two.

A Brief History of Antibiotics

Despite modern medical science improving lives for some three centuries, the history of antibiotics is relatively new. Alexander Fleming discovered penicillin (the first) in the 1920s. It led to a revolution in medical treatment of bacterial infections. As with many scientific discoveries, penicillin was accidental. He stacked together a number of staphylococci, bacteria that causes skin complaints in most mammals. He returned after a month-long holiday to see one of the cultures contaminated with a fungus around which the staphylococci was destroyed. Further research discovered that the fungus could kill a number of harmful bacteria; penicillin was born.

What is an Antibiotic?

There are many different types of antibiotic derived from different sources although most in present use are types of fungi. Essentially, they are substances that attack or eat bacteria, or simply halt their spread throughout a biological system. They are used against infections. Some are better for some conditions than for others which is why we have so many types.

AntibioticsHow each antibiotic works depends on the type your Doctor prescribed. The first major type is called “bactericidal”. This means they attack bacterial cells directly, killing them. These work by attacking the wall lining of the bacterial cell or the nucleus. In either case, the bacterium cannot reproduce and will eventually die off in the host body. Penicillin and several other major types work like this.

The other type of antibiotic is called “bacteriostatic”. Instead of killing the bacterial cell, they attack the mechanics of reproduction or interfere with the genetic makeup. This renders the bacteria’s reproduction impotent. The bacteria then cannot spread and will die off naturally. These types rely on the human immune system. They are therefore problematic for people with immune deficiency. Tetracycline is one type of antibiotic that works like this.

In brief, one type kills and the other type inhibits spread.

Why Won’t Antibiotics Work on Viruses?

Antibiotics work on bacteria as it infects a host body. It is a foreign substance that (in most cases) the body will fight off naturally. Sometimes we need extra help in the form of antibiotics. Viruses work differently from bacteria. Instead of infecting a body, the virus passes instructions to the human cell to replicate the virus instead of antibodies. Bacteria is a living organism but a virus is dead. You cannot kill something that is dead but you can kill a living organism – hence why antibiotics don’t work against viruses.

Why is Over Prescription Problematic?

There has been a lot of concern in the NHS and globally of the over-prescription of antibiotics. The first reason is that GPs don’t always have enough time to ascertain the origin of your illness. In a fifteen-minute consultation, your GP must determine whether you have a virus or a bacterial infection. On that basis, they must decide whether or not to prescribe antibiotics. If they wrongly prescribe you antibiotics, they risk contributing to the increased resistance of existing bacteria that were once effectively treated by that medication. If they don’t prescribe antibiotics and you have a bacterial infection, it can lead to further complications and illness.

The more antibiotics are overprescribed, the more resistant even simple bacteria will become. Conditions once easily treated have the potential to cause long-term health problems. It will also mean a lot of investment of time and money to find new treatments. This is a global problem with no simple solution.