symptoms of do allergy
Symptoms. Allergy symptoms depend on the substance involved and can involve the airways, sinuses and nasal passages, skin, and digestive system. Allergic reactions can range from mild to severe. In some severe cases, allergies can trigger a life-threatening reaction known as anaphylaxis.Hay fever, also called allergic rhinitis, may cause: 1  Sneezing. 2  Itching of the nose, eyes or roof of the mouth. 3  Runny, stuffy nose. 4  Watery, red or swollen eyes (conjunctivitis).llergic reactions can range from mild to severe. In some severe cases, allergies can trigger a life-threatening reaction known as anaphylaxis. Hay fever, also called allergic rhinitis, may cause: 1  Sneezing. 2  Itching of the nose, eyes or roof of the mouth. 3  Runny, stuffy nose. 4  Watery, red or swollen eyes (conjunctivitis).