Final answer:
Allergies are disorders in which the immune system reacts to harmless antigens called allergens. Common allergens include pollen, dust mites, and certain foods. Symptoms of allergies can include sneezing, runny nose, and itchy eyes.
Step-by-step explanation:
Allergies are disorders in which the immune system makes an inflammatory response to harmless antigens called allergens. Common allergens include pollen, dust mites, mold, certain foods, insect stings, and certain medications. Symptoms of allergies can vary but may include sneezing, runny nose, nasal congestion, itchy eyes, and skin rashes.