The parent mentioned Allergic Reaction. Many people, including non-native speakers, may be unfamiliar with this word. Here is the definition^{(In beta, be kind):}

Allergic reactions are sensitivities to substances called allergens that come into contact with the skin, nose, eyes, respiratory tract, and gastrointestinal tract. They can be breathed into the lungs, swallowed, or injected. [View More]

^{See also: Allergen | Tract | Intolerance | Severe | Skin | Fight | Sever | Packaging | Gifted}

^{Note: The parent (throwaway154229) can delete this post | FAQ}