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Learn in what circumstances antibiotics may be appropriate — and when they are not.

Source: Health Services

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Antibiotics (also called antibacterials) are a group of medications that specifically target bacteria.
Therefore, antibiotics are only prescribed to treat infections that are caused by bacteria and NOT viruses. They work by either killing harmful bacteria or by slowing down their growth.

Antibiotics are not effective against infectious diseases caused by micro-organisms other than bacteria
Infectious diseases can be caused by several groups of micro-organisms; organisms that are so small that they can't be seen by the human eye. These include bacteria (which cause chlamydia or gonorrhea), viruses (which cause the common cold or flu), fungi (which cause ringworm or athlete's foot) and parasites (which cause malaria or trichomoniasis). Only infectious diseases caused by bacteria can be effectively treated with antibiotics. There exist medications to treat infectious diseases caused by micro-organisms other than bacteria: antiviral medications treat viral infections; antifungal medications treat fungal infections; and antiparasitic medications treat parasitic infections.

Taking antibiotics for an infection that is not caused by bacteria has consequences
Several consequences are associated with antibiotic misuse (i.e. using antibiotics when they are not needed). These include:

  • Antibiotic resistance. When bacteria are frequently exposed to an antibiotic (through overuse or misuse), over time they become resistant to that antibiotic. As a result, an antibiotic that used to successfully treat an infection becomes useless: it no longer works. This is called antibiotic resistance and it has serious consequences. Because of antibiotic resistance, today people are dying from infections that were easily cured by an antibiotic.
  • Side effects. Antibiotics, like all medications, have side effects. When antibiotics are necessary, the benefits far outweigh the risks. However, when they are not needed a person takes an unneccesary risk of experiencing side effects.
    • Common side effects that include:
      • Diarrhea or soft stools
      • Upset stomach
      • Nausea
      • Vomiting
      • Fungal infections of the mouth, digestive tract or vagina
    • Rare side effects include:
      • Kidney stones
      • Abnormal blood clotting
      • Sensitivity to sunlight
      • Deafness
      • Blood disorders
      • Inflamed bowels with bloody diarrhea
      • Allergic reaction
  • Cost. Antibiotics are not free...they cost money. Insurance companies, Quebec Medicare and the individual all contribute to paying for antibiotics. In 2014, 23 million antibiotic prescriptions were filled in Canada. It is estimated that 50% of these prescriptions were unnecessary. That adds up to a massive amount of money that didn't need to be spent (i.e. wasted).

Do not pressure your health care provider to prescribe an antibiotic if they determine that it is not necessary
A health care provider uses their expertise, experience and a variety of tools to determine which microorganism is the cause of a patient's illness and then prescribe treatment based on that assessment. 

One of the major reasons why some doctors prescribe antibiotics is that their patient insists that they need an antibiotic. The World Health Organization lists some things that individuals can do to reduce the impact and limit the spread of antibiotic resistance. One of these is: "Never demand antibiotics if your health worker says you don’t need them"

Never take medication that was not specifically prescribed to you
You should never take a medication that is not prescribed to you, and this includes antibiotics. Doctors prescribe the amount and type of medication to treat a condition based on their medical assessment of the patient. Each case is different, so taking medication prescribed to someone else for a similar issue may not be appropriate for you.

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