Antibiotic Safety

You are sick and feel miserable. So you go to your doctor for antibiotics to kill what ails you. Instead, your doctor takes a different treatment route that does not include prescribing antibiotics. It's important to know that sometimes drugs can be more harmful than helpful.

When Medicine Meets Resistance

pill bottleMany things can give you an infectious illness, such as bacteria, viruses, fungi, or other microorganisms. The most commonly prescribed antibiotics only work against bacteria. Therefore, they will not be helpful if a virus or other microorganism causes your illness. When prescribed appropriately and taken correctly, antibiotics can be very effective. They can shorten the time you are sick and keep the disease from spreading to others.

Perhaps because they seem so effective, doctors may have a tendency to prescribe them too often, even when there is not anything for them to treat and you would have gotten better just as quickly without them. Sometimes this is done in the hopes of preventing bacterial infection. However, over time, many bacteria adapt to resist antibiotics, making these medications less effective or unable to work at all. This occurs even in bacteria not responsible for the illness that just live in your body.

Antibiotic resistance is harmful. As more antibiotics are introduced into our environment, by either over-prescribing or entering our food chain through their use in the dairy, poultry, and livestock industries, more strains of bacteria have the potential to become resistant. Examples of bacterial strains that are already resistant to antibiotics include:

Some bacteria may be resistant to only one antibiotic, while others are resistant to a range of antibiotics. Bacteria can pass this ability to resist multiple antibiotics on to other bacteria, even wihout the presence of antibiotics.

These multidrug-resistant bacteria create a challenge for doctors. Patients with conditions caused by these types of bacteria not only endure longer hospital stays, but they may also have to take many drugs in hopes that one of the medications or the combination of medications will work. Often these drugs can be toxic and ineffective. Patients infected with antibiotic-resistant bacteria are more likely to die from their illnesses.

To Prescribe or to Not Prescribe?

So when is an antibiotic right for you? That is for your doctor to decide. In cases when your doctor decides against antibiotics, it is most likely because a virus causes your condition or it will go away without medication.

A cold, the flu, and acute bronchitis are caused by viruses. Antibiotics are not useful in treating these conditions or their symptoms. In certain circumstances, a bacterial infection can develop during a cold or flu. In these situations, antibiotics may be prescribed.

Viruses also cause many runny noses, congested sinuses, coughs, and sore throats. These can also be caused by bacterial infections, so it is important to try to establish which. For example, if your sore throat is caused by bacteria, as in strep throat, your doctor will prescribe antibiotics, but using antibiotics for a viral sore throat may cause problems without providing any benefit.

Viruses or bacteria can cause middle ear infections. Your doctor will determine if antibiotic treatment is needed.

UTIs are most often caused by bacteria and are usually treated with antibiotics.

You may also be prescribed antibiotics if only bacteria are known to cause your illness or the cause is unknown and the doctor determines it is better to treat with antibiotics than not.

If Given Antibiotics…

If your doctor does decide to prescribe antibiotics, it is important that you follow all dosing instructions carefully and completely. This is true for any medications your doctor may prescribe.

  • Read the label on the medication bottle, along with any handouts your doctor gave you about your medication. Follow all instructions.
  • Do not share your medication.
  • Do not save your medication for when you get sick again. It is important to take all of your antibiotics, even if you start to feel better. Not finishing them may allow some of the infecting bacteria to remain alive in your body, which can cause another infection.

Although generally safe, if you are taking antibiotics there are some other things you should know:

  • Antibiotics might cause side effects or allergic reactions.
  • Antibiotics may change the effectiveness of other medications you are taking. This includes birth control pills.
  • There may be bad bacteria (the ones antibiotics are designed to fight), but there are also good bacteria, like the ones that live in our digestive system to help us break down food. Antibiotics cannot tell the difference and kill good bacteria in the process. This can cause upset stomach, diarrhea, vaginal infections in women, and other unpleasant symptoms.

It is important to tell your doctor if you are pregnant, think you may be pregnant, or are nursing. Certain antibiotics may be harmful to your baby.

Now that you are aware of why your doctor may or may not give you antibiotics, it is important that you continue to have open discussions about your treatment options. Ask questions. Share any information regarding your medical history. Discuss side effects that concern you. And if you do not understand something, speak up. Having a 2-way discussion will help your doctor plan the best treatment approach for you.


Centers for Disease Control and Prevention
Family Doctor—American Academy of Family Physicians


Canadian Medical Association


About antimicrobial resistance: a brief overview. Centers for Disease Control and Prevention website. Available at: Updated September 8, 2015. Accessed March 1, 2017.
Antibiotics. EBSCO DynaMed Plus website. Available at: Updated November 16, 2016. Accessed March 1, 2017.
Understanding antimicrobial resistance. NIAID website. Available at: Updated April 3, 2012. Accessed March 1, 2017.
What is antibiotic resistance and why is it a problem? Alliance for the Prudent Use of Antibiotics website. Available at:
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Accessed March 1, 2017.
Last reviewed February 2017 by Michael Woods, MD, FAAP
Last Updated: 3/1/2017

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