Many first report peanut allergy symptoms in adulthood, study finds

While a peanut allergy is commonly associated with pediatric care, a new study has found that up to one in six adults with sensitivity to peanuts developed it after age 18. The report, put forth by Northwestern University researchers in the Journal of Allergy and Clinical Immunology, found that 2.9% of U.S. adults report a current peanut allergy, but only 1.8% report a physician-diagnosed allergy and or history of reaction symptoms.

Additionally, among this group, two in three adults have at least one other food allergy such as tree nuts or shellfish. Researchers say the lack of physician-diagnosed allergy is concerning as that means patients do not have a current epinephrine prescription, possibly leaving them susceptible to severe reactions without having potentially life-saving treatment on hand.

The report, believed to be the first to provide an estimate of peanut allergy in adults, suggests that at least 4.5 million adults in the U.S. are impacted by the allergy.

"Unlike allergies such as milk or egg, which often develop early in life and are outgrown by adolescence, peanut allergy appears to affect children and adults to a similar degree," Christopher Warren, director of population health at Feinberg’s Center for Food Allergy and Asthma Research and co-first author said, according to a news release posted on Eurekalert.org.  "Our study shows many adults are not outgrowing their childhood peanut allergies, and many adults are developing peanut allergies for the first time."

The researchers also noted that the only approved therapy for peanut allergy is aimed at pediatric patients up to age 17 and called for more research into adult patients and additional therapies.

"Given the high prevalence of peanut allergy among U.S. adults, additional therapies are needed to help address this growing burden of disease," Dr. Ruchi Gupta, study author and professor of pediatrics at Northwestern University Feinberg School of Medicine and a physician at Ann & Robert H. Lurie Children's Hospital of Chicago, said in the Eurekalert.org news release.

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