Extrinsic asthma is caused by this type of immune system response to inhaled allergens such as pollen, animal dander or dust mite particles. On the other hand, Intrinsic asthma is caused by anything except an allergy. It may be caused by inhalation of chemicals such as cigarette smoke or cleaning agents, taking aspirin, a chest infection, stress, laughter, exercise, cold air, food preservatives or a myriad of other factors.
Asthma triggered by allergies is known as extrinsic asthma. It is also called allergic or a topic asthma. In this form of the disease, an asthma attack is clearly linked to the body's response to something inhaled or, occasionally, ingested. Substances to which the person is allergic are called allergens. Extrinsic asthma is commonly seen in children. About ninety percent of childhood asthma cases are due to allergens. Individuals with a family history of allergens are at more risk for extrinsic asthma.