OAS, also known as pollen-food syndrome, is a Class 2 food allergy. “You first become allergic to a pollen via inhalation, and then start reacting to foods that share similar proteins. So this food allergy is secondary to the pollen allergy.”
"...mouth itch when you eat...fruits? ...If you get this reaction to nuts, you should not assume it’s oral allergy syndrome,” Pomeranz said. The oral itching with nut allergies can be the same symptom that you’d get initially from a true food allergy. “And then you could get really sick the second time you tried it,” she said.
Understanding and Managing Your Pollen Allergies: Whether you are in the heart of allergy season or a less serious time of the year, there are plenty of steps you can take to build a strong defense again pollen.