Australians who have been told they are allergic to penicillin are being encouraged to discuss it with their doctor, with research showing up to nine in 10 people with a reported penicillin allergy are not allergic when properly assessed.¹
Around 10% of people report a penicillin allergy – equivalent to approximately 2.8 million Australians based on the current population – yet fewer than 1% of the population are thought to be truly allergic.¹ ²
Professor Michaela Lucas, a Clinical Immunology/Allergy Specialist and Co-chair of the National Allergy Council’s Drug Allergy Working Group said: “For many people, a penicillin allergy recorded after symptoms experienced during a childhood illness has followed them throughout their lives. We want people to understand that an allergy recorded years or even decades ago may be worth reassessing, rather than assuming they will always be allergic to penicillin.”
The National Allergy Council, a partnership between the Australasian Society of Clinical Immunology and Allergy (ASCIA) and Allergy & Anaphylaxis Australia, is raising awareness about reported penicillin allergy and encouraging people to consider whether an allergy recorded in the past may be worth revisiting.
The awareness campaign coincides with the release of new ASCIA guidelines, developed in collaboration with the National Allergy Centre of Excellence (NACE). The guidelines, together with online training and resources, support General Practitioners (GPs) and other health professionals to assess and manage reported penicillin allergy, including identifying people who may be suitable for penicillin allergy assessment by their GP.
Professor Lucas said there were several reasons why someone may have penicillin recorded as an allergy when they are not currently allergic.
“Someone may have developed a rash while taking penicillin and understandably it was assumed the antibiotic was responsible, when the rash may actually have been caused by the underlying illness or another factor,” Professor Lucas said.
“Even when someone did have a genuine allergic reaction, we know that sensitivity can diminish over time and may not be life-long. That doesn’t mean anyone should disregard a suspected allergy or try penicillin themselves. It means it is worth talking to your doctor about whether having it properly investigated may be appropriate for you.”
Why does it matter?
“The range of penicillin medications are often the preferred treatment for bacterial infections. If penicillin is recorded as an allergy, doctors need to prescribe alternative antibiotics, so knowing whether a patient is truly allergic means doctors can make the most appropriate treatment choice,” Professor Lucas said.
Reported antibiotic allergy is also associated with longer treatment and hospital stays, higher readmission rates and greater use of alternative antibiotics. Unnecessary use of alternative antibiotics can contribute to antimicrobial resistance, where bacteria become resistant to antibiotics.3
“Antimicrobial resistance matters beyond the individual patient because resistant bacteria can spread between people and through communities. If someone develops a serious infection that is resistant to several antibiotics, doctors can be left with very limited treatment options which further impact the persons health and wellbeing” Professor Lucas said.
How do you find out if you are allergic?
Ms Maria Said AM, Director and Co-Chair of the National Allergy Council, said for people who have been avoiding penicillin for years, finding out whether they are truly allergic may be more straightforward than they realise.
“The first step is to talk to your GP, who can review your medical history, including your symptoms and how long ago the reaction occurred, and determine whether further assessment may be appropriate.”
Dr Nick Cooling, GP, and Chair of the RACGP Specific Interest Group in Allergy, said the new guidelines would give GPs clearer guidance on assessing people with a reported penicillin allergy and identifying those who may be suitable for removing a penicillin allergy label in general practice.
“For some people considered at low risk of a serious allergic reaction, this may involve an oral penicillin challenge under medical supervision. The antibiotic is given in a medical setting, and you are closely monitored in case an allergic reaction happens, with the process generally taking around two hours. People that are not found to be allergic to penicillin then have an increased range of antibiotics to target specific infections.
“Those with a history suggesting a higher risk of penicillin allergy may need further testing and assessment by a specialist allergy service. No one should try taking penicillin themselves to find out whether they are allergic. Antibiotics should only be taken when prescribed for the individual taking them.”
About the National Allergy Council
The National Allergy Council is a partnership between the Australasian Society of Clinical Immunology and Allergy (ASCIA) and Allergy & Anaphylaxis Australia (A&AA), Australia’s peak medical and patient support organisations for allergic disease. Funding from the Australian Government Department of Health, Disability and Ageing enables the National Allergy Council, alongside ASCIA and Allergy & Anaphylaxis Australia, to deliver evidence-based public health initiatives, education, training and support in consultation with key stakeholders, to improve the health and wellbeing of people with allergic disease.
Penicillin allergy facts
Around 10% of people report a penicillin allergy, while less than 1% of the population are truly allergic.¹
More than 90% of people recorded as having a penicillin allergy can tolerate penicillin following appropriate assessment and testing.¹
Reported antibiotic allergy is associated with longer treatment and hospital stays, higher readmission rates and greater use of alternative antibiotics.³
Around 50% of people with a positive penicillin skin test lose that reactivity within five years, while around 80% of people with a true immediate penicillin allergy become tolerant after 10 years.¹
In Western Australian hospitals, up to 10% of children and 18% of adult inpatients have a recorded antibiotic allergy, with penicillin accounting for 79% of recorded antibiotic allergies in children and 71% in adults.⁴
An Australian economic evaluation found that, compared with usual care, low-risk inpatients who underwent penicillin allergy assessment and had the allergy removed had an average 4.41 fewer hospital days and $9,467.72 lower hospital costs per patient. The study was exploratory.⁵
References
Devchand M, Trubiano JA. Penicillin allergy: a practical approach to assessment and prescribing. Australian Prescriber. 2019;42:192–199. doi:10.18773/austprescr.2019.065.
Australian Bureau of Statistics. National, state and territory population, March 2026. Estimated resident population: 27,921,150 at 31 March 2026.
Arnold A, Coventry LL, Foster MJ, Koplin JJ, Lucas M. The Burden of Self-Reported Antibiotic Allergies in Health Care and How to Address It: A Systematic Review of the Evidence. Journal of Allergy and Clinical Immunology: In Practice. 2023;11(10):3133–3145.e3. doi:10.1016/j.jaip.2023.06.025.
Brusco NK, Bury S, Chua KYL, Vogrin S, Holmes NE, Trubiano JA. Penicillin Allergy Delabeling Program: an exploratory economic evaluation in the Australian context. Internal Medicine Journal. 2023;53(1):74–83. doi:10.1111/imj.15532.
Penicillin Allergy SHACK: Survey of hospital and community knowledge. Journal of Paediatrics and Child Health. 2022;58:1414–1419. doi:10.1111/jpc.16007.
