Symptoms of an allergic reaction to animals may include itchy skin, nasal congestion, itchy nose, sneezing, chronic sore throat or itchy throat, swollen, red, itchy, and watery eyes, coughing, asthma, or rash on the face or chest.
[citation needed] Allergies are caused by an oversensitive immune system, leading to a misdirected immune response.
The immune system normally protects the body against harmful substances such as bacteria and viruses.
Allergy occurs when the immune system reacts to substances (allergens) that are generally harmless and in most people do not cause an immune response.
[citation needed] This immunology article is a stub.