Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) allergic asthma ?
    ### Response:
    Asthma is a breathing disorder characterized by inflammation of the airways and recurrent episodes of breathing difficulty. These episodes, sometimes referred to as asthma attacks, are triggered by irritation of the inflamed airways. In allergic asthma, the attacks occur when substances known as allergens are inhaled, causing an allergic reaction.
    