Penicillin Allergy: Things You Should Know

Author: Allergy and Asthma Network
Published: 2016/12/18 - Updated: 2023/07/17
Publication Type: Informative
Category Topic: Allergies and Allergens - Academic Publications

Page Content: Synopsis - Introduction - Main

Synopsis: Information regarding penicillin allergy, being allergic to penicillin causes an abnormal reaction of the immune system to the antibiotic drug penicillin. Up to 10% of the population report being allergic to penicillin, according to the U.S. Centers for Disease Control and Prevention (CDC).

Introduction

Penicillin was originally discovered in 1928 by Scottish scientist Alexander Fleming. It wasn't until 1942 that it was used to treat infections in humans.

Today, there are several enhanced families of penicillin effective against additional bacteria they include:

Penicillin was considered a wonder drug when it was first introduced in 1928 - and it has revolutionized medicine ever since. We can now treat infections that used to be a death sentence.

Main Content

What if You Believe You are Allergic to Penicillin?

You may still have options.

Up to 10 percent of people report being allergic to penicillin, according to the Centers for Disease Control and Prevention (CDC). However, up to 90% of this group may not actually be allergic to penicillin. Serious allergies only occur in about 0.03% of the population. Persons who are allergic to penicillin are usually given a substitute known as cephalosporin C because of its functional groups.

"Understanding penicillin allergy is important," says Tonya Winders, president and CEO of Allergy & Asthma Network, the leading nonprofit patient education organization for people with asthma and allergies. "It kills 400 people a year. However, studies show many people who believe they are allergic to penicillin really are not. This mistaken belief leads to higher drug costs, inferior medical treatments and possible antibiotic resistance. If you think you are allergic to penicillin, see a board-certified allergist for testing. Don't wait until you're in a medical crisis."

Here are the top things the Network wants you to know about penicillin allergy:

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Sir Alexander Fleming (6 August 1881 - 11 March 1955) was a Scottish biologist, physician, microbiologist, and pharmacologist. His best-known discoveries are the enzyme lysozyme in 1923 and benzylpenicillin (Penicillin G) from the mould Penicillium notatum in 1928, for which he shared the Nobel Prize in Physiology or Medicine in 1945 with Howard Florey and Ernst Boris Chain. Sir Alexander Fleming wrote many articles on bacteriology, immunology, and chemotherapy.
Sir Alexander Fleming (6 August 1881 - 11 March 1955) was a Scottish biologist, physician, microbiologist, and pharmacologist. His best-known discoveries are the enzyme lysozyme in 1923 and benzylpenicillin (Penicillin G) from the mould Penicillium notatum in 1928, for which he shared the Nobel Prize in Physiology or Medicine in 1945 with Howard Florey and Ernst Boris Chain. Sir Alexander Fleming wrote many articles on bacteriology, immunology, and chemotherapy.
Continued...

Side Effects of Penicillin Antibiotics Can Include

  • abdominal pain
  • allergic reactions
  • black or hairy tongue
  • bleeding
  • confusion
  • diarrhea
  • dizziness
  • easy bruising
  • heartburn
  • insomnia
  • itching
  • nausea
  • rash
  • stomach cramps
  • vomiting

Serious but Rare Penicillin Reactions Can Include:

  • kidney problems
  • low blood platelet levels (thrombocytopenia) or red blood cell count
  • oral fungal infections
  • seizures
  • severe allergic reactions (anaphylaxis)

Reactions to penicillin may vary - including many additional symptoms not mentioned above - between different strains or types administered.

"Anyone who believes they are allergic to penicillin because they had a reaction years ago should undergo testing with a board-certified allergist," says Courtney Blair, MD, board-certified allergist in McLean, Virginia and Anaphylaxis Community Experts (ACE) volunteer with Allergy & Asthma Network. "If you are found to be allergic, then you'll have a confirmed diagnosis and will know what to avoid. If you're not, then you'll know that if you need penicillin, you can take it without concern."

When you're facing a medical treatment, you want the best possible care. Why limit your treatment to less effective drugs, or those with potentially more serious side effects? Talk with your physician about your past reactions with penicillin, and see a board-certified allergist to determine if testing is warranted.

The PALACE Study Looks at Reducing the Penicillin Allergy Label


Attribution/Source(s): This quality-reviewed publication was selected for publishing by the editors of Disabled World (DW) due to its relevance to the disability community. Originally authored by Allergy and Asthma Network and published on 2016/12/18, this content may have been edited for style, clarity, or brevity.

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Cite This Page: Allergy and Asthma Network. (2016, December 18 - Last revised: 2023, July 17). Penicillin Allergy: Things You Should Know. Disabled World (DW). Retrieved October 9, 2025 from www.disabled-world.com/health/respiratory/allergies/penicillin-allergic.php

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