A large Australian study indicates that oral food challenges in infants not only confirm peanut allergies but also can lead to de-labeling in over a third of cases, potentially easing dietary restrictions and guiding immunotherapy decisions.
A large Australian study suggests that oral food challenges can do more than confirm a peanut allergy in very young children: they may also clear the diagnosis in a substantial minority, allowing families to introduce peanut without continued avoidance. Researchers reviewing cases from 10 hospitals found that more than a third of infants under 18 months who had both a previous peanut reaction and evidence of sensitisation ultimately had a negative challenge, meaning they could be de-labelled and begin eating peanut regularly. The work, published online in The Journal of Allergy and Clinical Immunology: In Practice, adds weight to the growing view that supervised challenges remain the most reliable way to settle uncertain food allergy diagnoses.
The study, led by Kirsten P. Perrett of the Murdoch Children’s Research Institute in Parkville, Australia, examined infants seen between April 2024 and October 2025 as part of the country’s standard peanut oral immunotherapy pathway. Of 1,275 infants assessed, 778 underwent the threshold oral food challenge, which used seven gradually increasing doses of peanut protein. Just under two-thirds of those challenges were positive, with a median trigger dose of 120 mg of peanut protein. Anaphylaxis occurred in 7.8% of all challenges and in 12.0% of positive tests, but the researchers said the procedure was managed safely.
Among the 394 infants who then started immunotherapy at the dose identified by the challenge, 97.5% tolerated that first dose at the initial updosing visit. Only one child could not manage a 3 mg dose and was removed from the programme because a lower dose could not be given reliably. In practice, the findings suggest that a challenge can serve two purposes at once: it can distinguish infants who are truly allergic from those who are not, and it can help define a starting point for treatment when immunotherapy is planned.
The study also found that skin prick test wheal size and Ara h 2-specific IgE levels were higher in infants who reacted, but neither test could reliably predict the dose at which a reaction would occur or how severe it would be. That is consistent with recent review evidence showing that these tests may offer some guidance but remain too variable to replace an oral food challenge, which continues to be regarded as the diagnostic gold standard. The Australian researchers said the approach should be considered whether families are planning immunotherapy or simply trying to avoid unnecessary dietary restriction, arguing that accurate confirmation of peanut allergy can reduce the personal, family and wider burden created by misdiagnosis.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
