was tun bei einer allergischen reaktion — which blood markers matter?

During an acute allergic reaction, clinical management is paramount: antihistamines, corticosteroids, or epinephrine for anaphylaxis. Blood markers are most useful for follow-up or when the trigger is unclear. Key markers include: **Total IgE** (elevated in allergies but non-specific – also high in parasitic infections or hyper-IgE syndrome), **specific IgE** (≥0.35 kU/L is considered positive, but indicates sensitization only, not necessarily clinical allergy; up to 50 % of sensitized individuals tolerate the allergen without symptoms), and **tryptase** (acutely elevated in anaphylaxis, aids diagnosis of mast cell activation). **IgG testing** for food is not validated and should not be used to diagnose allergy or intolerance. Genetic tests (e.g., HLA variants) have effect sizes too small to be clinically useful. Important: A positive IgE result alone does not justify dietary elimination or medication – interpretation requires a board-certified allergist. Evidence: human-strong for IgE in allergy diagnosis, but with caveats (sensitization ≠ allergy).