What is Allergy?
[[File:What happens when you are allergic.webm|thumb|Analytical chemist Georgina Ross ([[Wageningen University & Research]]) about allergies ]] An '''allergy''' is something which triggers an '''allergic reaction'''. This is the [[immune system]] defending the [[body]] against attack by [[bacteria]] and [[virus]]es. Having an allergy is when a thing (called an allergen) cannot enter the body without them getting sick. Sometimes the system goes wrong, and is triggered by some normal food, or flares up when the family pet comes into the room. This is what the ordinary person calls an 'allergy'. == 'Allergic reactions' == When people come in contact with something they are allergic to, there can be many different reactions. These reactions include the face and [[skin]]: itchy eyes, [[Runny nose|drippy]] or [[Stuffy nose|stuffy noses]], swollen face, and develop a rash called hives. It can affect the [[respiratory tract]]: sneezing, and [[coughing]]. If it is a food allergy, the person may get an upset stomach. Sometimes a person's [[oesophagus]] (throat), may swell up so much that the person can no longer breathe. This is called [[anaphylaxis]]. When this happens, a doctor must give the person a [[medicine]] called [[epinephrine]] to make the swelling go down. Some people with allergies to very common things, like [[bee]] stings or [[fish]] or nuts, carry this medicine with them so it can be used quickly in an emergency. The device used to treat allergies and inject the medicine is called an epinephrine autoinjector. == Common allergies == Some common food allergies are: * Nuts, especially [[Peanut|peanuts]] * Fish or [[shellfish]] * [[Dairy product|Dairy]] products * [[Egg (food)|Eggs]] * Products of [[Soybean|soy]] * [[Wheat]] * [[Fruit|Fruits]] (kiwis and bananas, [[avocado]]) Some common environmental allergies are: * [[Latex]] - these allergies can overlap with fruit allergies, or develop through exposure to latex * [[Pollination|Pollen]] * [[Ragweed]] * [[Mold]] * Furry [[pet]]s, fluffy housing de