Childhood Anaphylaxis Study Reveals a Two-Sided Adrenaline Problem

Anaphylaxis is the allergic reaction every parent dreads: a child eats a food or takes a medication, and within minutes the body launches a full-scale immune assault that can close the airway and drop blood pressure to lethal levels. The recommended first-line treatment is simple and decades old, an intramuscular injection of adrenaline, yet real-world hospitals consistently struggle to get the timing right. A new cross-sectional study from Hangzhou Children’s Hospital in China, published in BMC Pediatrics, offers a detailed look at how pediatric anaphylaxis actually presents and how often the lifesaving drug is given correctly. The findings expose a dual problem that clinicians everywhere will recognize: some children receive adrenaline too late, while others receive it when they should not need it at all.

The research team, led by Chao Chen of the hospital’s Pediatric Intensive Care Unit and corresponding author Xuefeng Jin of the Department of Gastroenterology, retrospectively analyzed 115 pediatric patients treated for anaphylaxis between January 2021 and October 2024. The dataset covered age, gender, suspected triggers, allergy history, clinical manifestations, treatments administered, adverse reactions, and outcomes. To probe the safety profile of adrenaline itself, the researchers also collected adverse reaction data from 70 children who received intramuscular adrenaline for reasons unrelated to anaphylaxis. That second cohort matters, because a persistent barrier to prompt adrenaline use in emergency settings is fear of the drug’s side effects, particularly in small bodies. By examining children who received adrenaline outside the anaphylaxis context, the study could test whether that fear is grounded in reality.

What the team found about triggers will not surprise allergists, but the proportions are instructive. Food allergens were the leading suspected cause, implicated in 52 of the 115 cases, or 45.22 percent. Drug allergens came second at 34 cases, or 29.57 percent. Only 37 of the 115 children had a documented prior history of allergy, a striking statistic given that anaphylaxis is often assumed to strike children with known allergic profiles. In practice, a majority of the children in this cohort were experiencing a severe reaction without any prior warning on their medical record. That gap between expectation and reality is precisely what makes anaphylaxis so difficult to diagnose in pediatric emergency departments, where a first presentation may look like an ordinary allergic reaction until breathing difficulties escalate.

The clinical picture that emerged from the case records was dominated by two organ systems. Skin and mucosal involvement was the most common manifestation, present in 108 of 115 patients, or 93.91 percent, and it typically appeared as urticaria, the raised, itchy welts commonly called hives, or as angioedema, the deeper swelling of tissues beneath the skin. Respiratory symptoms were a close second, occurring in 104 patients, or 90.43 percent, with presentations that included cough, wheezing, dyspnea, and laryngeal edema, the swelling of the voice box that represents one of the most dangerous features of anaphylaxis in children. The near-universal overlap of skin and breathing symptoms underscores why pediatric guidelines emphasize that anaphylaxis is a clinical diagnosis: when hives appear alongside any respiratory compromise after a plausible exposure, the clock starts immediately.

Against that backdrop, the adrenaline data tell a nuanced story. Intramuscular adrenaline was administered to 101 of the 115 patients, or 87.83 percent, and 91 patients, or 79.13 percent, received it as first-line treatment. On one level, those numbers are encouraging, since they suggest that the majority of children in this Chinese tertiary pediatric hospital were treated in line with international guidelines that place adrenaline at the front of the protocol. On another level, the remaining gap is significant. Roughly one child in eight did not receive the drug at all, and about one in five did not receive it first, despite the drug being the single intervention most strongly associated with survival in anaphylaxis. Every minute of delay allows airway swelling and vascular collapse to progress, and delayed administration is one of the most consistently documented failures in anaphylaxis care worldwide.

The safety findings may prove to be the study’s most consequential contribution. Across both the anaphylaxis group and the 70 children who received intramuscular adrenaline for non-anaphylaxis indications, no adverse reaction was observed. Not one significant adverse event was reported in any of the children treated with adrenaline. For a drug whose perceived danger often delays its use, that result is a pointed rebuttal. Adrenaline, or epinephrine as it is known in much of the world, is a naturally occurring hormone and neurotransmitter, and when delivered intramuscularly at pediatric doses it produces a transient physiological response rather than the dangerous arrhythmias clinicians sometimes fear. The fear, the data suggest, is largely inherited from outdated practice patterns involving intravenous administration rather than from the intramuscular route recommended today.

The authors frame the problem as a dual challenge: delayed adrenaline administration on one side and excessive prophylactic use on the other. The second half of that equation deserves attention. In settings where adrenaline is given reflexively to children whose reactions do not meet the criteria for anaphylaxis, the drug loses its signal value and clinical teams risk normalizing unnecessary interventions. The Hangzhou dataset, which deliberately included non-anaphylaxis adrenaline recipients, was designed to illuminate exactly this tension. Balancing the two errors, under-treatment and over-treatment, requires better diagnostic precision at the bedside, not more caution in one direction or the other. The study’s conclusion points toward a pragmatic resolution: given how difficult anaphylaxis is to diagnose in children, early administration of adrenaline when the condition is strongly suspected on clinical grounds may help optimize management overall.

Why does diagnosis remain so hard in children? Part of the answer lies in the presentation data itself. Urticaria and angioedema are extremely common in pediatric allergic reactions that never progress to anaphylaxis, so their presence alone does not settle the question. Respiratory symptoms such as cough and wheezing overlap heavily with viral infections, asthma exacerbations, and even foreign-body aspiration, all far more frequent than anaphylaxis in a busy pediatric emergency department. A clinician weighing whether a wheezing child with hives is experiencing anaphylaxis must integrate exposure history, reaction tempo, and evolving symptoms in minutes. The fact that only about a third of the children in this cohort had a known allergy history compounds the difficulty, because a blank allergy history can falsely reassure. Diagnostic uncertainty, not ignorance of the guidelines, is the engine of both delayed and excessive adrenaline use.

The study’s retrospective, single-center design means the numbers describe one hospital’s experience over nearly four years rather than a national picture, and cross-sectional analyses cannot establish causation or capture long-term outcomes. Still, the granularity of the dataset, spanning triggers, manifestations, treatment sequencing, and a dedicated safety cohort, makes it a useful mirror for pediatric departments anywhere. The core takeaways travel well: food and drugs cause the overwhelming majority of pediatric anaphylaxis, skin and respiratory signs dominate the presentation, most children arrive without a prior allergy diagnosis, and intramuscular adrenaline, given promptly, appears remarkably safe even beyond its intended indication. For parents, the practical lesson is that a child with hives plus any breathing difficulty after a food or medication warrants immediate emergency assessment, not watchful waiting. For clinicians, the message is subtler but equally clear: the evidence continues to favor giving adrenaline early when anaphylaxis is strongly suspected, because in this dataset the drug’s risks never materialized while the costs of hesitation remain written into the treatment delays the authors documented.

Subject of Research: Adrenaline use and clinical characteristics of anaphylaxis in children

Article Title: Clinical characteristics and adrenaline use in anaphylaxis in children: a cross-sectional study

Article References: Chen, C., Jin, X., Cai, J., Wang, J., Zhang, C., & Tang, W. (2026). Clinical characteristics and adrenaline use in anaphylaxis in children: a cross-sectional study. BMC Pediatrics. https://doi.org/10.1186/s12887-026-07643-3

Image Credits: AI Generated

DOI: 10.1186/s12887-026-07643-3

Keywords: anaphylaxis, children, adrenaline, epinephrine, food allergens, drug allergens, pediatric emergency care, urticaria, angioedema, cross-sectional study, BMC Pediatrics, allergy