Bronchial hyperreactivity

The lungs of these patients are hyper reactive: they shrink too when triggers are present, this results in a decrease in their caliber. The air goes wrong, it does not happen much in the alveoli, oxygen can get in short supply and the body will be more or less in hypoxia that is to say lack of oxygen.

Allergies often cause asthma

Allergies are the main factors that promote the onset of asthma.
Sure pollen allergens are: there all year. Confined atmospheres are also conducive to the emergence of crises like the unventilated rooms, dusty, humid. The allergens are dust mites, cockroach droppings, mold. The animal hair (cats, dogs, horses) are also highly allergenic.