Allergies are widespread. About 20% of people are affected by allergic rhinitis and about 20% have atopic dermatitis at some point in their life, in the developed countries. Rates of many allergies appear to be constantly increasing.

Allergic diseases, are a number of conditions caused by hypersensitivity of our immune system to substances that usually cause no problem in most people. These conditions include food allergies, hay fever, allergic asthma and anaphylaxis. Symptoms may be a runny nose, sneezing, red eyes, swelling or shortness of breath. 

Average allergens are for example pollen and particular food. Insect stings, medications and food might be causes of severe allergic reactions.

Diagnosis is based on a person’s medical history, skin and blood tests.

Treatments include avoiding known allergies and medications such as antihistamines, steroids and adrenaline pens. Allergen immunotherapy, which gradually exposes people to larger and larger amounts of the known allergen, is quite successful for some types of allergies such as reactions to insect bites and hay fever.