An allergen is a typically harmless substance that triggers an abnormal or hypersensitive immune response. Is Called an allergy. Allergies come in a variety of forms. Dust mites, pet dander, foods, pollen, insect stings, and some medications.These area the reasons for common allergies. An allergic person’s immune system overreacts to an allergen, resulting in the… Continue reading Pest Control and Allergies: The Hidden Link