Allergies are a common yet enigmatic phenomenon that affects a large proportion of the population worldwide. They occur when our immune system , whose main function is to defend against diseases and infections, mistakenly interprets a harmless substance as if it were harmful, triggering a response that can range from a mere inconvenience to a potentially fatal situation.

These substances, called allergens , can be as diverse as pollen, bee venom, animal hair, or even certain foods that most people consume without any problem. Why does our body react this way?

And how can we manage these uncomfortable and sometimes alarming episodes?

We have therefore created this practical guide, very compact in each topic so that you can learn about the world of allergies and how they affect millions of people around the world.