The things that set off allergic reactions are called allergens. Common allergens are pollen, pets, moulds and dust mites. People can also be allergic to certain types of food – for example, nuts or eggs. It is possible to be allergic to more than one thing.
Eczema, asthma, hayfever and rhinitis are all allergic disorders.
An allergy develops when your body reacts to the allergen (for example, grass) as though it is a threat to your health. Your body produces antibodies to fight off this threat, and you might have a runny nose, itchy eyes or sore throat.
Who has allergies?
Lots of people have allergies, including children. Some allergens, such as foods, are a problem all year long, but others might only bother people at certain times of the year – for example, if you get hayfever, you are allergic to pollen, which is only around in the air in the spring and summer.
People can develop allergies when they are babies, children, teens, or adults, although allergies often affect older people less.
What are the symptoms of an allergy?
If you have an allergy or are allergic to a certain type of food, you could have:
- A head full of snot
- Itchy eyes and ears
- A runny nose
- A sore throat
- Breathing problems, like wheezing and shortness of breath
- Bad allergic reactions that need hospital treatment
- Hives (a red, bumpy and itchy skin rash)
- Tummy ache