Medically reviewed by Jurairat J. Molina, MD Allergies are an immune system reaction to substances called allergens. The cause a range of symptoms from a stuffy nose to itchy eyes to difficulty ...

which is delayed-type hypersensitivity. Symptoms may range from mild allergic responses, such as hives and itching, to severe conditions like anaphylaxis or autoimmune diseases. Understanding the ...

ALLERGIC rhinitis (AR) is a prevalent upper airway condition caused by an IgE-mediated type 1 hypersensitivity reaction to ...