What is allergy? Name the common allergens that cause allergies in human beings.

1. An allergy occurs when a person has a hyper-response or hypersensitivity to a particular antigen or substance.
2. Allergens are substances that cause allergies.
3. The following are some of the most common allergens: Pollen, animal dander, dust mites, and mould are examples of airborne allergens.
4. Food allergens such as peanuts, wheat, soy, fish, shellfish, eggs, and milk.
5. Stings of bees or wasps.