In a manner relating to anaphylaxis, a severe and rapid allergic reaction; in a way that involves heightened immune sensitivity.
From anaphylaxis (Greek ana- back + phylaxis protection) + -ic + -ally, describing severe reactions against protection.
Anaphylaxis is called a 'backwards' reaction because it's the immune system protecting you so aggressively it actually harms you—like your body's security guard attacking an innocent visitor.
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