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Why Antibiotics May Be Harmful

Monday, September 3, 2018

By Brian Holland PharmD, BCPS

When used appropriately, antibiotics save lives. But any time antibiotics are used, they can cause side effects and lead to antibiotic resistance – the inability of an antibiotic to kill bacteria.

According to the Centers for Disease Control and Prevention (CDC), antibiotic resistance is one of the world’s most pressing public health problems. Every time a person takes antibiotics, susceptible bacteria are killed leaving behind resistant bacteria that can grow and multiply. These resistant bacteria can also be spread to other individuals.

The CDC estimates that each year in the United States, more than 2 million people are infected by bacteria that cannot be treated by the recommended antibiotic and more than 23,000 of these people die.

A growing concern from the misuse of antibiotics has been Clostridioides difficile (formerly known as Clostridium difficile) infection, often referred to as C. diff or CDI. CDI results in inflammation of the colon, known as colitis. Symptoms of CDI include watery diarrhea, fever, loss of appetite, nausea and abdominal pain and tenderness. The CDC estimates that around a half-million people get infected with CDI each year in the United States, and approximately 20,000 of them die. Antibiotics are the leading cause of CDI.

It is estimated that about a third of all antibiotic prescriptions outside of a hospital setting are unnecessary. This amounts to more than 80 million unnecessary antibiotic prescriptions in the U.S. each year. Total inappropriate antibiotic use approaches 50 percent when you factor in inappropriate antibiotic selection, wrong dose and improper length of treatment.

Most of these prescriptions are for respiratory infections caused by viruses. Colds, bronchitis, most sinus infections and sore throats, and even some ear infections are caused by viruses. Antibiotics have no effect on viruses.

Drug-related adverse reactions – side effects – are an under-appreciated consequence of antibiotic use. A recent national study showed antibiotics were implicated in nearly 20 percent of all emergency room visits for drug-related adverse events.

In addition to the development of bacterial resistance, the use of antibiotics changes our microbiome; those are the beneficial bacteria living in us that help keep us healthy. A healthy microbiome supplies our bodies with important nutrients, helps with vitamin production and protects us from unhealthy or disease-causing bacteria. Alterations in the human microbiome has been associated with a large number of health problems including childhood obesity, diabetes, asthma and increased risk of infections.

When used as they should be, antibiotics do their job very well. It’s vitally important to follow the orders of your health care provider regarding antibiotics and to not misuse them.

About the author: Brian Holland, PharmD, BCPS, is Pharmacy Clinical Coordinator at Sky Lakes Medical Center Pharmacy.Brian Holland, PharmD, BCPS