Penicillin Allergy Prevalence Greater in High-Income vs. Middle-Income Nations

A study showed that high-income countries had a greater prevalence of penicillin allergy than middle-income countries.1

“Notably, as has been described previously, we found very little data from outside high-income countries, and we only found a single study published from a [low-middle-income country] and none from [low-income country],” wrote investigators, led by Akish Luintel, PhD, from Imperial College London, St Mary's Hospital, in London.

For instance, Africa and most of Asia and South America had little data on penicillin allergy prevalence.

Patients labeled with penicillin allergy often receive broad-spectrum antibiotics, which are linked to antimicrobial resistance and poorer outcomes. However, approximately 95% of patients are likely mislabeled with this allergy.

Lately, de-labeling programs have been growing but only in selected countries. Even in the US, the incorrect allergy label persisted in electronic medical records or pharmacy records despite efforts of de-labeling programs, as seen in a 2019 study.2

Investigators conducted a systematic review and meta-analysis to assess the global prevalence of penicillin allergy, intending to understand the potential impact of de-labeling programs.1 The team reviewed all studies on the prevalence of penicillin allergy among adults between January 2003 and June 2023, leveraging data on penicillin allergy prevalence, allergy recording methods, healthcare settings, and country income.

Out of the 18,353 studies screened, 174 studies from 28 countries were included. Most studies were from high-income countries (92%), with 72% from the US, UK, or Australia. More than 50% of studies were conducted in the US alone.

High-income countries included the US, Canada, UK, France, Netherlands, Spain, Portugal, Belgium, Denmark, Norway, Estonia, Finland, Italy, Latvia, Russia, Slovenia, Oceania, Australia, New Zealand, and Saudi Arabia. Upper-middle-income countries included Mexico, Turkey, China, and Colombia. The only included low-middle-income country was Pakistan.

The global prevalence of penicillin allergy was 9.4% (95% confidence interval [CI], 8.4 – 10.4%). High-income countries had a 9.9% prevalence of penicillin allergy (95% CI, 8.7 – 11.0%), which was significantly greater than the 4.4% penicillin allergy prevalence in middle-income countries (95% CI, 2.8 – 6.2%) (P < .0001).

Investigators wrote the low data on penicillin allergy prevalence in certain continents, such as Africa, Asia, and South America, may suggest penicillin allergy in these places has a lower burden and thus receives less research. One study conducted in Africa found the prevalence of penicillin allergy labels was 4.12%. Likewise, research conducted in Vellore, India observed an overall antibiotic allergy label of 3%, indicating a lower rate of reported penicillin allergy.

“These studies indicate potentially lower prevalence rates outside Western [high-income countries],” investigators wrote. "However, with so few studies from these areas, expansion of data is critical, prior to drawing further conclusions.”

Countries where English is the primary language—US, UK, Australia, and Candia) had prevalence levels of ≥ 10%; no other countries reached this prevalence. Investigators speculated that reported penicillin allergy may stem from language, ethnicity, or cultural factors.

The study observed that the method of allergy recording significantly impacted the reported prevalence. For instance, penicillin allergy was reported more from specific allergy modules of the electronic health record systems or manual chart view/questionnaires than datasets using coding such as ICD-10. This indicates that coding may not be completed as comprehensively as a chart for reporting penicillin allergy.

Furthermore, few studies were conducted in primary care (6.5%; 95% CI, 0.2 – 20.5%) compared with secondary care (10.2%; 9.2% - 11.3%).

Investigators believed this could be because penicillin allergy is likely to be managed by secondary care physicians and many studies examined the effect of penicillin allergy on surgical outcomes, explaining why there was a lot of hospital data. Some countries also have less primary care than secondary care so patients are seen directly by specialists.

Still, primary care research is underrepresented in the literature. Investigators stressed the importance of removing or preventing incorrect labels in primary care.

“This shift in focus could potentially lead to more effective strategies for managing penicillin allergy and improving antibiotic stewardship practices,” investigators wrote. “More generally, work should be done in primary as well as secondary care even in [high-income countries], especially given the number of antibiotics prescribed here.”

References

1. Luintel, A, Healy, J, Blank, M. The Global Prevalence of Reported Penicillin Allergy: A Systematic Review and Meta-Analysis. Journal of Infection. Vol. 0, Issue 0, 106429. 2025.
2. Gingerich, C. Patient Fears, Records Reduce Penicillin Allergy De-labeling Efforts. HCPLive. February 24, 2019. https://www.hcplive.com/view/patient-fears-records-reduce-penicillin-allergy-delabeling-efforts. Accessed January 28, 2025.