Antibiotics 101

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Mary thinks she may have a bladder infection. She makes the call to her doctor and is able get an appointment to come in and give a urine sample. Sure enough, bladder infection. Her doctor prescribes an antibiotic for the infection. Mary goes to the pharmacy, fills the prescription and as she is driving home, begins to think of questions that she should have asked her doctor about the antibiotic.

This scenario has run through many patients' minds. What are the side effects of the antibiotic? How soon should I begin to feel better? What if I don't feel better after 4 or 5 days? When should I call my doctor? Should I be concerned about a rash or other side effects that develop while taking the antibiotic?

Antibiotics 101

Antibiotics are a class of drugs that treat bacterial infections by stopping growth of bacteria or killing the bacteria directly. It's important to remember that antibiotics are ineffective in treating infections causes by viruses, which include the majority of colds, sore throats (with the exception of streptococcus-induced, or so-called "strep throat"), coughs, and flu-like illnesses.

In fact, taking antibiotics when they are not really necessary will not speed your recovery and can even contribute to a problem known as antibiotic resistance. Antibiotic resistance refers to the capacity of many bacteria to become resistant to a particular antibiotic so that it is no longer effective against these bacteria. It is known that the increasing use of antibiotics when they really aren't needed has contributed to this problem and has led to the evolution of many bacterial strains that no longer respond to treatment with common antibiotics; a phenomenon known as antibiotic resistance.

The evolution of antibiotic-resistant strains of Staphylococcus aureus [methicillin-resistant Staph aureus or MRSA, and vancomycin-resistant enterococci (VRE)] has received much attention in recent years, and a new strain of the bacterium Clostridium difficile, which can cause intestinal illness in people taking antibiotics for other conditions, has arisen which is much more difficult to treat and is associated with a higher death rate.