While not everyone who has asthma has allergies, those who do are at risk of developing an asthma attack when their allergies are triggered. About 70 percent of the 28 million Americans with asthma do have some type of allergy, though. When your allergies are set off, an antibody called immunoglobulin E is released. It attacks the invading allergen and your body releases histamine, among other chemicals. Histamine is responsible for most allergic symptoms.

The most common allergens that set off asthma are those related to hay fever: pollen, dust mites and pet dander. You can end up with nasal congestion, a runny nose, itchy eyes and itchy skin. When your lungs or airways get blocked or they narrow, breathing becomes more difficult. In turn, your asthma kicks in and you end up coughing, wheezing and with shortness of breath as you suffer both allergic and asthmatic symptoms. Avoiding allergens can help reduce the risk of allergy-induced asthma attacks.