Dietary consumption of peanut after completing oral immunotherapy (OIT) or sublingual immunotherapy (SLIT) for peanut allergy may actually provide continued protection against accidental exposures to the allergen, according to a new study led by Edwin Kim. The findings were presented in the annual American Academy of Allergy, Asthma and Immunology (AAAAI) conference in San Francisco.
The study followed 55 people who had completed OIT or SLIT peanut immunotherapy trials at UNC-Chapel Hill and were desensitised to between 300mg and 5,000mg of peanut. Notably, desensitisation increases the amount of peanut it takes to cause an allergic reaction, decreasing the likelihood of a severe reaction caused by accidental peanut exposure.
Speaking about it, Kim says, “They don’t necessarily want to eat large amounts of their allergen, they just want a level of reassurance that if a restaurant cook makes a mistake or a food label is wrong, they won’t have a severe allergic reaction.”
After completing their immunotherapy trial, participants were encouraged to introduce foods containing peanuts into their diets with a goal of about 300mg of peanut each day. As part of their long-term follow-up, participants were asked to report how much they ate, how often they ate it and how they felt afterward.
The majority of participants continued regularly eating peanuts daily for up to eight years after completing immunotherapy. Among those still eating peanuts, the median amount of daily consumption was 600mg. No reactions from accidental ingestions were reported for the 55 participants, but 10 people reported allergic reactions to the daily peanut foods they introduced into their diet. The majority of reactions were mild and treated with antihistamines; however, three reactions required epinephrine and two required EMS.
Although these more significant reactions were infrequent, it is a reminder that incorporation of dietary peanut in this capacity should only be done under the guidance of an allergist. Kim says more longitudinal studies need to be done, but he and colleagues are hopeful this research can be applied to other types of food allergies.