-- Question: What are common symptoms of allergies?
Answer: Allergies are caused by an imbalance in a person's immune system resulting from exposure to an environmental substance or allergen which when present may cause a wide range of symptoms. When a person is allergic to one of these substances, their immune cells release a substance called histamine.
When the allergen comes into contact with an antibody that was created from an earlier exposure. The result may include symptoms such as runny nose, nasal congestion, itching or pruritus of the eyes, nose, and throat, and skin hives, and in the most severe conditions, difficulty breathing. Some of the common allergic responses include hay fever, hives, eczema, asthma, food allergies and reactions to insect bites.
Once again, the underlying problem in each of these reactions is that an individual has an exaggerated response to a substance that he has been exposed to previously, whereas in normal conditions, the immune system would not produce such symptoms. Common allergens are prevalent in everyday life, such as tree pollens, grass, dust mites, cockroaches and molds.