Allergy

An allergy is something which triggers an allergic reaction. This is the immune system defending the body against attack by bacteria and viruses. 

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, drippy or 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 peanuts
 Fish or shellfish
 Dairy products
 Eggs
 Products of soy
 Wheat
 Fruits (kiwis and bananas, avocado)

Some common environmental allergies are:

 Latex - these allergies can overlap with fruit allergies, or develop through exposure to latex
 Pollen
 Ragweed
 Mold
 Furry pets, fluffy housing decorations, or bedsheets and pillows etc.
 Bee or wasp stings
 Dust mites
 Tobacco smoke
 Pollution

Related pages
 Histamine
 corticosteroids

 References 



Category:Allergies