The majority of allergic reactions in kids are accidental — typically due to caregivers' forgetfulness or lapses in supervision — but 1 in 9 reactions are triggered by giving known allergens intentionally, a study finds.

Most young kids with allergies to foods like milk or eggs are still having allergic reactions, even after parents and caregivers have been informed of the children’s allergies, a new study finds — and about 11% of these incidents aren’t accidental.

The findings come from an ongoing government-sponsored study that has been following more than 500 children aged 3 to 15 months with food allergies since they were infants. The families filled out detailed questionnaires about allergic reactions and symptoms and underwent several clinical evaluations.

Over the course of the 36-month study period, nearly 72% of the kids had at least one allergic reaction; just over half of the kids experienced more than one. The most common reactions were to milk, eggs or peanuts, and of these 834 cases, the vast majority (87%) were accidental, attributed to lapses like forgetfulness or lack of supervision on the part of the caregiver (65%), label-reading errors (16%) and unintentional cross-contamination (15%) or mistakes in preparation (4%) of foods.

Only about half of the accidental reactions were caused by food given by parents, so the data suggest that other caregivers — like babysitters, grandparents and teachers — need to be better informed about kids’ allergies.

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About 1 in 9 cases of allergic reaction were intentional, however, and the authors of the study aren’t sure why caregivers would purposely give kids a known allergen. “Maybe parents were testing their children to see if they had outgrown their allergy,” Dr. David Fleischer of National Jewish Health in Denver and lead author of the study told ABC News. “There’s going to be a follow-up study, going back to families and asking exactly why caretakers were giving these foods on purpose.”

If parents want to try reintroducing allergic foods, experts say they should consult an allergy expert first.

The researchers were also concerned by caregivers’ failure to administer epinephrine when children had severe reactions. About 11% of the kids in the study experienced anaphylaxis, which includes symptoms like swelling in the throat, asthma, sudden drop in blood pressure, dizziness and fainting. Parents and caregivers used an EpiPen in only 30% of such cases.

In some cases, parents and caregivers were too afraid to administer the epinephrine injection, or they didn’t think the reaction was severe enough to warrant it and waited for further symptoms. In other cases, epinephrine wasn’t available.

“The lesson here is that we as doctors need to make sure we talk to families about the safety of the medication. It maybe makes people jittery, but so does coffee,” says co-author Dr. Scott Sicherer, a professor of pediatrics and chief of the division of allergy and immunology at Mount Sinai School of Medicine in New York. “[Epinephrine] reverses all the severe symptoms and gives you time to get to the emergency room before it gets worse.”

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The study is the first to gauge the frequency and reasons for allergic reaction in children even after their families have been informed and counseled about how to avoid them. Researchers sought to identify gaps in parent education, especially since foods allergies affect up to 8% of children — and are rising — and reactions can be severe or fatal.

“This study reinforces the importance of educating parents and other caregivers of children with food allergy about avoiding allergenic foods and using epinephrine to treat severe food-allergic reactions,” said Sicherer in a statement. “We must work harder to thoroughly educate parents about the details of avoidance and when and how to correctly use epinephrine to manage this life-threatening condition.”

The study was published in the journal Pediatrics.

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