The etiology of asthma is not well understood, and the factors that contribute to its onset include genetic and environmental factors. Most asthma patients are allergic, and genetic factors are evident in many patients, such as a history of asthma or other allergic diseases (allergic rhinitis, atopic dermatitis) that can be traced among the relatives of the vast majority of patients. Environmental factors, common airborne allergens (mites, pollen, pets, molds, etc.), certain foods (nuts, milk, peanuts, seafood, etc.), bacterial and viral infections, climate change, exercise, etc. may be triggering factors for asthma.