When kids are sick, we want a quick solution. While antibiotics can be lifesaving if used in the right situation, they aren’t always appropriate. Dr. Elizabeth Wolf, a pediatrician, researcher and mom, answers some key questions about when antibiotics are the right choice for treatment and why it’s important to avoid them when they aren’t.

When and how should antibiotics be used

How do antibiotics work?

Antibiotics fight bacterial infections by killing the bacteria directly or slowing its growth. They can do this by either attacking the wall around bacteria or interfering with its reproduction.

What is the difference between bacterial and viral infections?

This can get confusing because both types of organisms, viruses and bacteria, are too small to be seen without a microscope – but viruses are even smaller than bacteria. The biggest virus is still smaller than the smallest bacteria. Viruses are also different in that they cannot live without a host, whereas bacteria can exist on their own.

Viral infections include chicken pox, the viruses that cause the common cold and, of course, coronavirus. Examples of bacterial infections are strep like you would find in strep throat and many skin and wound infections.

Antibiotics are designed to fight bacterial infections. They’re not effective against viruses, including the flu or COVID-19.

When where antibiotics first discovered?

Antibiotics were first discovered in the 1920s when Dr. Alexander Fleming found that one of the molds growing in his petri dish was inhibiting the growth of a certain type of staph. Staph is the bacteria that causes boils or abscesses. Penicillin was the first antibiotic to usher in this modern era of medicine.

How are over-the-counter medicines like Advil or Tylenol different from antibiotics?

Ibuprofen and acetaminophen – or the brand names Advil and Tylenol – are medicines that treat symptoms of an infection, like pain or fever. But antibiotics kill the bacteria itself. So those over-the-counter medications can help kids feel better, but they won’t get rid of bacteria causing the illness.

Is there a downside to prescribing antibiotics?

Antibiotics are one of the most amazing creations in medicine – before antibiotics, there were no effective treatments for deadly infections like pneumonia or bacterial meningitis. But with widespread use of these medications, a problem began to emerge. Antibiotics killed not just the bacteria they were targeted against, but many other types of bacteria as well. When this happens, it can actually raise the rates of resistance to antibiotics in the community. That means these bacteria evolve so certain forms of antibiotics are no longer useful against them – and some bacteria can even evolve to have resistance against multiple antibiotics.

Antibiotics can also kill “good” bacteria in the gut and alter the microbiome – or the trillions of microorganisms that impact the body’s day-to-day functioning. Much is still being learned about this subject, but there is growing evidence that alteration of the microbiome can leave the body more susceptible to developing certain autoimmune diseases.

How do you determine when to prescribe an antibiotic and which one is the best option?

We only prescribe antibiotics when we need to, which is when we're treating a bacterial infection that will not get better on its own. We are also selecting the narrowest antibiotic possible, meaning we want the antibiotic to be targeted to the types of bacteria that are causing the person’s illness. At CHoR, and at many other hospitals, we’ve established clinical guidelines to help medical providers choose the right antibiotic so we're not giving kids antibiotics that are too broad.

Are there certain times when it’s important for kids to start an antibiotic regimen immediately and other times you might recommend waiting?

Yes. There are certain conditions, such as bacterial meningitis, where getting an antibiotic promptly after diagnosis can make the difference between life and death. But in certain conditions in pediatrics, we do have the option to wait. One example is an ear infection. In a child older than 2 years old who doesn't have severe pain or fever, particularly if the ear infection is only on one side, we can wait and see if it gets better on its own. Many ear infections are actually viral in which case an antibiotic wouldn’t help anyway.

Do antibiotics have side effects? Are there ways to prevent them?

There is a risk of side effects with every medication we use. Another reason to choose the narrowest spectrum antibiotic is that they can have fewer side effects. Amoxicillin is an example of a relatively narrow spectrum antibiotic, but even amoxicillin can disrupt the body’s microbiome and lead to troubling side effects like diarrhea. Some suggest using probiotics to shorten the course of an antibiotic-associated diarrhea and get the body’s microbiome back into shape.

Is there any other place our children are exposed to antibiotics aside from when they’re prescribed?

One way we’re all exposed to antibiotics is through food. Farmers often feed antibiotics to livestock because small amounts of antibiotics can help the animals gain weight. The problem is that studies have shown these antibiotics can then contribute to antibiotic resistance in bacteria, and those resistant bacteria can then be transferred to humans. So, we really need to remember that as humans we’re part of a larger ecosystem that can impact our health and well-being.

Listen to Dr. Wolf’s podcast about kids and antibiotics.