Hay Fever - Overview 

Most likely you or someone you know has allergies. The telltale itchy, puffy, watery eyes and red, stuffy nose signal changes in the seasons in homes and workplaces across the country. What these people  suffer from is allergic rhinitis, or  hay fever. The medical name for this condition refers to stuffy and itchy nose ("rhin-"),  the most common symptom. 

Hay fever is  an allergic reaction. It is your immune system's response  to foreign material in the air you breathe. Hay fever usually refers  to allergies  to outdoor, airborne materials such as pollens and molds. 

About 15-20%  of the population of the United States has some degree of hay fever. It is found equally  in both men and women. Usually hay fever is seasonal, but it can last all year long if  the allergen stays throughout the year. Spring and fall  are the main hay fever seasons. 

Hay Fever Causes 

Hay fever, like  all allergic reactions,  is caused by allergens, foreign "invaders"  that enter your body by inhalation, by swallowing, or through your skin. 

• In hay fever,  the allergens are airborne substances that enter your airways (mouth, nose, throat, and lungs) via your breathing and the linings of your eyes and sometimes ears via direct contact.   
• Most of the time it is difficult to identify  a specific allergen. 
• Once these allergens come in contact with your airway, the white blood cells  of your immune system produce antibodies to the offending substance. This overreaction to a harmless substance is often called a hypersensitivity reaction. 

1. The antibody, called immunoglobulin E, or IgE, is stored on special cells called mast cells. 
2. When the antibody comes in contact with the corresponding antigen, they promote release  of chemicals and hormones called "mediators." Histamine is  an example of a mediator. 
3. It is the effects of these mediators on organs  and other cells that cause the symptoms of the  allergic reaction, in this case hay fever. 

• The most common allergens  in hay fever are pollens. 

1. Pollen  is small particles released by flowering plants. 
2. It is moved  around by wind to other plants of  the same species, which it fertilizes so that  the plant can bloom again. 
3. Pollens from certain types of trees, grasses,  and weeds (such as ragweed)  are most likely to cause reactions. Pollens from other types  of plants  are less allergenic. 
4. The time of year when a particular species of plant releases pollen,  or "pollinates," depends on the local climate and what it normal for that species. 

                             Some species pollinate  in the spring  and others  in the late summer and early fall. 
                             Generally, the farther north  a plant is, the later in the season it pollinates. 

        5.   Variations in temperature  and rainfall from year  to year affect how much pollen is in  the air in any given season. 

• The other common allergens in hay fever are molds. 

1. Molds are a type of fungus that has no stems, roots, or leaves. 
2. Mold spores float through the air like pollen until they find a hospitable environment to grow. 
3. Unlike pollen, however, molds do not have a season. They are present throughout the year in most of the United States. 
4. Molds grow both outdoors and indoors. 

      Outdoors, they thrive in soil, vegetation, and rotting wood. 

      Indoors, molds (usually called mildew) live in places where air does not circulate freely, such as attics and basements, moist places such as bathrooms, and places where foods are stored, prepared, or discarded. 

• The amounts of pollen and molds in the air are measured daily in many areas around the United States and reported by the National Allergy Bureau. 

1. The pollen and mold counts at which people develop allergic symptoms vary quite a lot by individual. 
2. Pollen and mold counts are not very helpful in predicting how a specific person will react. 

• Risk factors for hay fever 

1. Family members with hay fever 
2. Repeated exposure to the allergen 
3. Other allergic conditions such as eczema or asthma 
4. Nasal polyps (small noncancerous growths in the lining of the nose) 

• The allergens that cause symptoms in an individual as he or she ages. Symptoms decrease in some allergy sufferers, but not all, as they grow older. 
• Bodily changes of pregnancy may make hay fever worse. 

Hay Fever Symptoms 

The usual symptoms of hay fever include the following: 

• Sneezing
• Runny nose (clear, thin discharge) 
• Congested ("stuffy") nose 
• Postnasal drip 
• Sensation of plugged ear(s) 
• Watery, bloodshot eyes 
• Itching of  nose, soft palate, ear canal, eyes, and/or skin 
• Fatigue
• Trouble sleeping 

When to Seek Medical Care 

Call your health care provider if you experience any of the following: 

• Symptoms that do not improve with self-treatment 
• Fever that does not subside 
• Nasal secretions that are colored, thickened, or bloody 
• Sore throat that gets worse 
• Earache or ear discharge 

Go to the hospital emergency department if you experience any  of the following in conjunction with an allergic reaction: 

• Very high fever 
• Difficulty breathing 
• Uncontrolled bleeding 
• Discharge from the ear or severe earache