Allergies & Hay Fever
Doctor, Please Explain Allergies and Hay Fever
Why does the body develop allergies?
Allergy symptoms appear when the immune system reacts to an allergic substance that has entered the body as though it was an unwelcomed invader. The immune system will produce special antibodies capable of recognizing the same allergic substance if it enters the body at a later time.
When an allergen reenters the body, the immune system rapidly recognizes it causing a series of reactions. These reactions often involve tissue destruction, blood vessel dilation, and production of many inflammatory substances including histamine. Histamine produces common allergy symptoms such as itchy, watery eyes, nasal and sinus congestion, headaches, sneezing, scratchy throat, hives, shortness of breath, etc. Other less common symptoms are balance disturbances, skin irritations such as eczema, and even respiratory problems like asthma.
What allergens should be avoided?
Many common substances can be allergens. Pollens, food, mold, dust, feathers, animal dander, chemicals, drugs such as penicillin, and environmental pollutants commonly cause many to suffer allergic reactions.
One of the most significant causes of allergic rhinitis in the United States is ragweed. It begins pollinating in late August and continues until the first frost. Late springtime pollens come from the grasses, i.e., timothy, orchard, red top, sweet vernal, Bermuda, Johnson, and some bluegrasses. Early springtime hay fever is most often caused by pollens of trees such as elm, maple, birch, poplar, beech, ash, oak, walnut, sycamore, cypress, hickory, pecan, cottonwood, and alder. Colorful or fragrant flowering plants rarely cause allergy symptoms because their pollens are too heavy to be airborne.
Certain allergens are present all year long. These include house dust, pet danders, some foods and chemicals. Symptoms from these are frequently worse in the winter when the house is closed up and where there is poor ventilation.
Mold spores can also cause allergy problems. Molds are present all year long, and grow outdoors and indoors. Dead leaves and farm areas are common sources for outdoor molds. Indoor plants, old books, bathrooms, and damp areas are common sources of indoor mold growth. Mold is also common in foods, such as cheese and fermented beverages.
How can allergies be managed?
Allergies are rarely life threatening, but often cause lost work days, decreased work efficiency, poor school performance, and a negative effect on the quality of life. Considering the millions spent on antiallergy medications and the cost of lost work time, allergies cannot be considered a minor problem.
For some allergy sufferers symptoms may be seasonal, but for others it is a year-round discomfort. Allergy symptom control is most successful when multiple management approaches are used simultaneously. They may include minimizing exposure to allergens, desensitization with allergy shots, and medications.
If used properly, medications, including antihistamines, nasal decongestant sprays, steroid sprays, saline sprays, and cortisone-type preparations, can be helpful. Even over-the-counter drugs can be beneficial, but some may cause drowsiness.
When should a doctor be consulted?
The most appropriate person to evaluate allergy problems is an otolaryngologist (ear, nose, and throat specialist). Aside from gathering a detailed history and completing a thorough examination of the ears, nose, throat, head, and neck, the doctor will offer advice on proper environmental control and evaluate the sinuses to determine if infection or structural abnormality (deviated septum, polyps) is contributing to the symptoms.
In addition, the doctor may advise testing to determine the specific allergen that is causing discomfort. In some cases immunotherapy or allergy shots may be recommended. Immunotherapy is a unique treatment because it induces the build up of protective antibodies to specific allergens.
Tips for reducing the exposure to common allergens:
Wear a pollen mask when mowing grass or house cleaning (most drugstores sell them).
- Change the air filters regularly in heating and air conditioning systems, and/or install an air purifier.
- Keep windows and doors closed during heavy pollen seasons.
- Rid the home of sources of mildew.
- Don’t allow dander-producing animals (i.e., cats, dogs, etc.) into the home and bedroom.
- Change feather pillows, woolen blankets, and woolen clothing to cotton or synthetic materials.
- Enclose mattress, box springs, and pillows in plastic barrier cloth.
- Use antihistamines and decongestants as necessary and as tolerated.
- Sleep with the head of the bed tilted upward. Elevating the head of the bed helps relieve nasal congestion.
- Observe general good health practices: exercise daily, do not smoke, avoid air pollutants, eat a balanced diet, and supplement diet with vitamins, especially C.
- Use a humidifier in the winter. Be sure to clean the humidifier regularly to avoid mold build-up.
- Discuss hay fever and allergy symptoms with a physician when experiencing an allergic reaction.
©1996. American Academy of Otolaryngology-Head and Neck Surgery, Inc. This leaflet is published as a public service. The material may be freely used for noncommercial purposes so long as attribution is given to the American Academy of Otolaryngology-Head and Neck surgery, Inc., One Prince Street, Alexandria, VA 22314-3357
See our entire Allergy & Sinus Services section for much more information.