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Penicillin Allergy Frequently Asked Questions (FAQ)

This document has been developed by ASCIA, the peak professional body of clinical immunology/allergy specialists in Australia and New Zealand. ASCIA information is based on published literature and expert review, is not influenced by commercial organisations and is not intended to replace medical advice. For patient or carer support contact Allergy & Anaphylaxis Australia or Allergy New Zealand

pdfASCIA PC Penicillin Allergy FAQ 2023126.29 KB

Q 1: What does it mean if you are labelled with a penicillin allergy?

There are several types of penicillin antibiotics available, which are important for treating bacterial infections.

Many people are told that they have a penicillin allergy, or think that they have penicillin allergy, and are ‘labelled’ as having a penicillin allergy in their medical records. However, studies have shown that up to nine in ten of these people do not have a true penicillin allergy.

Therefore, it is important to find out if you have a true penicillin allergy, so that you can receive the best treatment when you have a bacterial infection.

Q 2: Why does this happen?

People are often told that they have penicillin allergy, or think that they have penicillin allergy:

  • After having symptoms such as rash, itching, or stomach upset while taking penicillin. These symptoms can be due to other causes, including a side effect of penicillin or a rash from the illness itself (for example, a viral infection such as flu or glandular fever), rather than a true penicillin allergy.
  • If they have a family member with possible penicillin allergy.
  • Even if they may have outgrown a penicillin allergy, but do not know this, and are still incorrectly labelled with a penicillin allergy.

Q 3: How can you get tested for penicillin allergy?

If you have been told that you have penicillin allergy, or think that you have penicillin allergy, your doctor may refer you to a clinical immunology/allergy specialist for testing, to confirm if you have a true penicillin allergy.

The tests ordered and interpreted by your specialist can include blood allergy tests, skin allergy tests and/or antibiotic challenge testing.

Q 4: What happens if tests show that you do NOT have penicillin allergy?

If allergy testing shows that you do NOT have a penicillin allergy, your doctor may prescribe penicillin or related antibiotics in the future, to ensure effective and efficient treatment of bacterial infections.

Q 5: What happens if tests show that you have penicillin allergy?

If a true penicillin allergy is diagnosed after testing:

  • You must avoid the penicillin that you have tested positive to. However, even if you are allergic to one type of penicillin, you may be able to safely take other types of penicillin as there are several types of penicillin antibiotics. Otherwise, alternative antibiotics should be prescribed when you have a bacterial infection.
  • Your penicillin allergy needs to be recorded in hospital, GP and specialist records and where possible, uploaded to your My Health Record.
  • Your doctor may complete an ASCIA Action Plan for Drug (Medication) Allergy and wearing a medical identification alert should be considered.

Q 6: What are the benefits of being tested for penicillin allergy?

Being told that you have a penicillin allergy or thinking that you have a penicillin allergy when you do not have true penicillin allergy can mean that alternative antibiotics need to be used. These can result in longer treatment times, increased risk of side effects and higher healthcare costs.

If you have been labelled with a penicillin allergy, talk to your healthcare provider about being tested to find out if you have a true allergy. This information can help ensure that you receive the most effective and efficient treatment of bacterial infections.

Q 7: Where can further information be obtained?

Fast Facts about Drug Allergy

Antibiotic Allergy Challenges FAQ

Antibiotic Allergy Challenges Consent Form

© ASCIA 2023

Content developed April 2023

For more information go to www.allergy.org.au/patients/drug-allergy

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