Despite high prevalence, diagnosis of the specific source of allergic reactions can be difficult, because various allergens often cause similar manifestations, such as respiratory or gastrointestinal symptoms. (truehealthdiag.com)
The skin of a patient with atopic dermatitis becomes easily irritated by various allergens such as certain types of food, pollens or house mites. (scilifelab.se)
After ruling out the other possible causes mentioned above such as food allergy and fleas, a veterinarian could test the dog for various allergens using an ELISA or RAST test in the same way humans are tested for allergies. (dog-health-guide.org)