Internal factors (factors that are based inside the human body itself) causing allergies include heredity, sex, race and age. External factors (factors that are based in the surrounding or the environment) include alterations in exposure to infectious diseases during early childhood, environmental pollution, allergen levels and dietary changes.

Dark circles under and around the eyes Recurring headache Shortness of breath Cough Diarrhea Stomach cramps Wheezing Asthma Itchy, watery eyes Itchy, runny nose Itching, eczema and/or hives

Ayurveda regards allergy as a disorder caused by impaired digestion, which is why preliminary symptoms may include indigestion, constipation or diarrhea. This dysfunction in the digestive process is the cause of the hypersensitivity to certain substances, such as dust and pollen that triggers the allergic attacks. Deposits of ama (toxins in the form of mucus) in the lungs and respiratory tract create obstruction in breathing and cause wheezing, coughing or sneezing.