| Hay fever is an allergic reaction to airborne particles | | | | substances that are harmless to most people -- like |
| that primarily affects the nose and eyes. | | | | pollen, mold, and pet dander -- and launches an |
| It is caused by outdoor allergens, and perennial allergic | | | | assault. |
| rhinitis by indoor allergens. Symptoms of hay fever | | | | This attack is called an allergic reaction. In an allergic |
| resemble a cold, except that they occur only at | | | | reaction, substances called histamine (among other |
| particular times: during certain seasons or weather | | | | chemicals) are released. Histamines contribute to the |
| patterns (hay fever), and around certain animals or | | | | symptoms of Symptoms include runny nose, itchy |
| small household pests (perennial allergic rhinitis). | | | | eyes, itchy skin. |
| Millions of people are affected by allergic rhinitis. Many | | | | Seasonal allergic rhinitis is caused by an allergic |
| people who have allergic rhinitis also have asthma. | | | | reaction to pollens and spores (depending on the |
| Causes of Hay Fever | | | | season and area) as they are carried on the wind. |
| The body's immune system is designed to fight | | | | Sources include: |
| harmful substances like bacteria and viruses. But hay | | | | Ragweed |
| fever, the immune system overresponds to | | | | |