- a serious condition in which the body identifies some sometimes quite harmless substances as harmful and potentially dangerous. Such substances are commonly called allergens. When a person comes into contact with an allergen, his immune system triggers defense processes, which are often manifested by cough, rash, runny nose and so on.
That is, for the occurrence of allergies, an allergen is necessary - a substance.
The severity of allergies depends on the individual characteristics of the body, it can manifest itself as you like: with slight irritation, and anaphylactic shock (deadly condition).
At the same time, it is rather difficult to predict the “response” of the body to a particular allergen: even if a person always has the same reaction to a product, it cannot be ruled out that at some point the reaction will be much stronger and much more dangerous. That is why, if you have a suspicion of an allergy, you must consult a doctor.
To diagnose an allergy and identify an allergen, coughing and a runny nose is not enough (even if it seems to a person that he has tracked a causal relationship). For this, the doctor will prescribe studies. For example, sometimes it is skin testing, sometimes a blood test for specific antibodies that are produced by the immune system in response to an allergen.
It is important to take into account that both false positive and false negative results are possible.