Antibiotic Allergies Can Be Unexpected and Dangerous

Health Topics

Allergic reactions to antibiotics are something you can develop over time. They might not affect you the first time you take a medication. Or, you could have been allergic to a medication in the past, but forgotten before you take it again.  

Either way, antibiotics are the most common cause of life-threatening immune-medicated drug reactions, according to the National Institutes of Health.  

If you take an antibiotic and think you’re having an allergic reaction, the first step is to know the difference between medication side effects and an actual allergy, says Clinical Nurse Practitioner Karin Benner of Middletown Family Practice, part of Premier Physician Network

“Side effects would be an upset stomach, diarrhea, nausea, maybe a little bit of a skin rash if you’ve been out in the sun,” she says. “An allergic reaction is a little more serious. In an allergic reaction, you can have things such as hives, itching, and a skin rash.” 

An antibiotic allergy can develop into something more severe – an anaphylactic reaction. This can cause:

  • Drop in blood pressure
  • Nasal congestion
  • Rapid heartbeat
  • Shortness of breath

If you have any of these reactions, seek medical attention right away, because they could become more severe.

“It’s very important not to ignore an allergy to antibiotics, because they can get more severe as time goes on,” Benner says. “Your body builds antibodies against that particular antibiotic, and so the response of your immune system is stronger every time and can shorten the length of time it takes to react. It can result in death, even in just minutes, if you ignore it.”

While an allergic reaction can happen right away or within just a couple hours of taking an antibiotic, it also can take up to two weeks after finishing the medicine. So, make sure to get medical help if you have any allergy symptoms during or within a couple weeks after antibiotic use.

If you know you’re allergic to a medication, tell your provider so they can prescribe you an option from a different class of antibiotics.

Antibiotic Overuse

For about 20 years, antibiotics were overused and prescribed too often. Taking antibiotics when not needed kills normal bacterial flora, weakening the body’s ability to fight allergies.

“It’s really important not to overuse antibiotics because while antibiotics do kill the bad bacteria, they also kill the good bacteria that we naturally have to fight with our own immune system,” Benner says. “If we overuse them, we’re destroying our body’s natural defenses and making it possibly harder to fight future infections.”

To learn more about antibiotic allergies, talk to your doctor or health care provider or search for a provider.

Click play to watch the video or read video transcript.

Karin Benner, APRN-CNP, FNP-C, MBA, CCM

Karin Benner, APRN-CNP, FNP-C, MBA, CCM

Middletown Family Practice

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