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Updated September 12, 2014.

Antibiotics were deemed "miracle drugs" in the 1940s, but there are several misunderstandings about what they do and how they work. Find out 5 common misconceptions about antibiotics and the truths behind the myths.

Myth: Deemed the “miracle drug” in the 1940s, antibiotics are the cure-all of virtually any infectious disease.
Reality: Antibiotics only work on infections by bacteria, not viruses. Some fungi and parasites may be susceptible to certain antibiotics.


 

Myth: Prescribed antibiotics can be stopped when symptoms subside
Reality: It is absolutely essential to follow your doctor’s orders when it comes to taking antibiotics. Failure to complete doctor’s orders can result in reinfection or the emergence of antibiotic-resistant bacteria, which can be far more deadly and more difficult to conquer (see above).
 

Myth: Antibiotics can be taken as preventative measures against some infections, such as while traveling overseas.
Reality: There is more harm than help in taking antibiotics when you aren’t sick. By using antibiotics when they aren’t needed, there is an increased risk of wiping out your body’s natural flora and making it prone to infection by pathogenic bacteria. Moreover, it is guaranteed that some bacteria (which may include those that cause disease) will survive during antibiotic treatment. These bacteria will be antibiotic-resistant, causing even more problems in the long run (see above).
 

Myth: Doctors can diagnose a bacterial infection during physical examination and prescribe antibiotics accordingly.

Reality: There are only a few signs that distinguish a bacterial infection from that of a virus or other infectious agent. However, it is not that easy to determine that an infection is bacterial without conducting additional tests. In most cases, infection by bacteria should be verified prior to antibiotics, but it is generally left to the doctor’s discretion. Prescribing antibiotics for a viral infection runs the risk of producing unnecessary side effects. For example, using amoxicillin to treat mononucleosis (“the kissing disease”), which is caused by a virus, can result in a whole body rash.
 

Myth: It is better to use items that are deemed “antibacterial” (such as antibacterial soaps, toothbrush handles, socks, etc.)
Reality: Some “antibacterial” items are fine to use, as long as they don’t contain antibiotics. Overuse and misuse of antibiotics can result in emergence of antibiotic-resistant strains of bacteria, which have their own slew of problems (see above).