Allergic asthma is a type of asthma that causes symptoms when a person is around certain triggers, for example, pet dander. These allergens lead to an immune system response that affects the lungs and makes it harder to breathe. According to the American Academy of Allergy, Asthma, & Immunology, allergic asthma is the most common asthma type. Allergies can be dangerous if they cause a life-threatening response known as anaphylaxis. In allergic asthma, as well as nonallergic asthma, an asthma attack, or exacerbation, can also be fatal occasionally. As a result, a person may wish to talk to their doctor about identifying asthma triggers to reduce the likelihood of an attack.