These are just guidelines, but they are the things your doctor will look for along with signs found on physical examination to help distinguish whether allergies are the source of symptoms.
Allergic rhinitis affects millions of children in the United States and is felt to be responsible for over 2 million lost school days and over one billion dollars spent on visiting the doctor and medications each year. With all these people affected, you can see why there are a lot of prescription and over-the-counter medications in the market trying to get your business. But to understand the role of medications and other interventions used to help alleviate the symptoms of allergic rhinitis, it is best to get an idea of what causes the allergies in the first place.
Our bodies have elaborate ways to distinguish what is part of our body and what is foreign. One of the ways it does this is through specific proteins of the immune system called immunoglobulins. There are a number of types of immunoglobulins many of which are involved in recognizing bacteria and viruses to help keep infection at bay. Then there are others that recognize foreign material that is in the air and are involved in causing the allergic reactions. These immunoglobulins (called IgE) are found on the cells that line the mucous membranes of the nose and eyes. These cells, called mast cells, are full of chemicals that are released and set off a chain reaction which eventually ends up giving the runny nose, sneezing, and watery/itchy eyes.