Allergy :An allergy is a specific reaction of the bodys immune system to anormally harmless substance, one that does not bother most people.People who have allergies often are sensitive to more than onesubstance.Allergic reaction :Normally, the immune system functions as the bodys defense againstinvading germs such as bacteria and viruses. In most allergicreactions, however, the immune system is responding to a false alarm.When an allergic person first comes into contact with an allergen, theimmune system treats the allergen as an invader and gets ready toattack.
The signs and symptoms of airborneallergies are familiar to many: Sneezing, often with a runny orclogged nose Coughing and postnasal drip Itching eyes, nose, and throat Watering eyes Conjunctivitis
Severe allergic reactions (anaphylaxis) needto be treated with a medicine calledepinephrine, which can be life saving whengiven right away. If you use epinephrine, call 911and go straight to the hospital. The best way to reduce symptoms is toavoid what causes your allergies. This isespecially important for food and drug allergies. There are several types of medications toprevent and treat allergies. Which medicine yourdoctor recommends depends on the type andseverity of your symptoms, your age, andoverall health. Illnesses that are caused by allergies (suchas asthma, hay fever, and eczema) may needothertreatments.