Allergic Reactions: Most Kids Can Skip Lengthy ER Stays
New Study Finds Routine Observation Times Often Unnecessary
Parents facing a child’s anaphylactic episode can breathe easier: a large new study reveals that the vast majority of children treated with epinephrine don’t require extended hospital observation, potentially freeing up valuable emergency room resources.
Shorter Stays, Safer Outcomes
Research involving over 5,600 children at 31 hospitals across the United States and Canada indicates that 95% of patients could be safely discharged within two hours of receiving epinephrine, and 98% within four. The findings, published June 10, 2025, in Lancet: Child and Adolescent Health, challenge current practices in many emergency departments.
Historically, nearly all children experiencing anaphylaxis were admitted for observation. While practices have evolved, many hospitals still routinely monitor patients for over four hours, particularly if any cardiovascular symptoms are present. “Our study suggests that 95% of patients could have been safely discharged two hours after receiving their first epinephrine dose and that 98% could have been safely discharged four hours after the first epinephrine dose,”
says the study’s lead author, Tim Dribin, MD, an emergency medicine physician at Cincinnati Children’s.
According to the CDC, food allergies affect approximately 8% of children in the United States, with peanut allergy being the most common. CDC Food Allergy Information
Understanding Biphasic Reactions
A key concern driving prolonged observation is the possibility of a biphasic reaction – a recurrence of symptoms after initial treatment. However, the study found that the need for a second epinephrine dose typically arises quickly. 4.7% of patients received a second dose within two hours, and only 1.9% needed one after four hours.
“Years ago, we used to admit virtually all kids with anaphylaxis to the hospital. We have stopped doing that, but most hospitals still routinely observe kids for over four hours, some even longer. And almost all hospitals admit kids if they have any signs of cardiovascular involvement.”
—Tim Dribin, MD
Streamlining Emergency Care
The research team analyzed data from 5,641 emergency visits, with 90% of reactions triggered by foods like peanuts, eggs, milk, shellfish, sesame, gluten, and soy. Approximately 6% were medication-related, and 3% stemmed from insect stings. While nearly 17% of children were admitted overnight, most didn’t require a second epinephrine dose or intensive care.
David Schnadower, MD, MPH, director of the Division of Emergency Medicine at Cincinnati Children’s, emphasizes the importance of efficient emergency department flow. “Pediatric emergency departments can get crowded quite quickly, especially during winter infection season. We need to ensure efficient throughput to allow us to provide access to as many patients as we can,”
he stated.
Hugh Sampson, MD, an allergist at the Icahn School of Medicine at Mount Sinai in New York City, added that reducing observation times could encourage families to seek prompt medical attention. “We also have seen patients and their families avoid or delay going to the emergency department because they didn’t want to sit there for hours of observation. Such delays can prove dangerous.”
The study was funded by the National Center for Advancing Translational Sciences and The National Institute of Allergy and Infectious Diseases.