Asthma may be triggered by allergies: 
There is little doubt that asthma is an allergic disease triggered by allergens. These allergens include not only foods, pollens, and environmental factors such as perfume, animal dander, and chemicals, but also bacteria, climatic conditions, and emotions. How early in life can the symptoms appear?: 
When these allergies are active from birth, asthma may develop early in life, even in infancy. When allergies are hidden and chronic, they may cause other chronic functional and developmental problems, such as fatigue, coughing, or headaches. What happens when asthma becomes chronic?: 
Chronic allergies cause bronchial tissues to break down slowly with minimal secretion of immune mediators, causing only minor muscle contraction, swelling, and increased mucus secretion in the bronchus. When other stressful factors are added to the system–for example, menopause, emotional stress, medication use, or gastritis–the person's allergic load is increased, and late-onset asthma may occur.