was machen bei allergischer reaktion — what are common causes?

Allergic reactions occur when the immune system overreacts to normally harmless substances called allergens. Common causes include pollen (hay fever), dust mites, animal dander, mold, insect stings, certain foods (e.g., peanuts, milk, eggs), and medications (e.g., penicillin). Symptoms range from sneezing, itching, and rash to life-threatening anaphylaxis. Genetic factors can influence susceptibility: variants in genes like IL1B or FCER1A are associated with higher allergy risk, but the effect is small and not deterministic. A DNA test may indicate a predisposition but cannot diagnose allergies. Environmental factors, early allergen exposure, and the microbiome often play a larger role. For acute reactions, antihistamines or corticosteroids are used; severe allergies require an epinephrine auto-injector. Allergen-specific immunotherapy (desensitization) can provide long-term relief. If you suspect an allergy, consult an allergist for proper testing and management.