Most people suffer no ill effects from this annual event, but as many as one person in three becomes allergic to the proteins delivered by pollen. When a person makes IgE antibodies to pollen proteins, the stage is set for spectacular problems. IgE antibodies bond to tissue mast cells, the cells that make, store and release histamine and other inflammatory mediators. In an allergic person, pollen proteins bind to IgE antibodies. Instantly the mast cells become activated and release histamine. This results in nasal itching, sneezing, watery secretions and obstruction. Eye, ear, sinus, throat and lung problems may appear as well. When the nose is rendered unable to filter the pollen out of the inspired air, 10-100 times more pollen is diverted to the throat and lungs.
How can people defend themselves against tree pollen-induced allergy? Avoidance, medication and immunotherapy in sufficient measure allow the spring to be enjoyed without limitation. Avoidance measures include travel to a region without tree pollen for the duration of the spring, keeping windows closed in cars and buildings, avoiding outside exposures during mid-day hours and on windy days, and wearing a high-efficiency filter mask. Avoidance is effective to some degree, but the idea is to defeat the problem rather than to be ruled by it.
Modern medications for allergic rhinitis fall into two categories: those that relieve symptoms (fast, but temporary relief) and those that suppress the allergic reaction (slow but powerful and longer lasting effects). Antihistamines have been improved to provide good effects on sneezing, itching and secretions while not causing drowsiness. Over-the-counter antihistamines and allergy remedies are less powerful and can cause drowsiness and impaired judgment, but are readily accessible remedies for mild disease. Symptomatic medications have a quick onset of action. These are particularly good "bad day" medications.
Topical anti-inflammatory drugs are the backbone of modern therapy for more severe allergic rhinitis because they are considerably more powerful. Cortisone-like drugs have been developed that are very active when sprayed into the nose, but which are rapidly degraded if absorbed into the body. The advantages of steroids can be obtained without systemic side effects. Cromolyn sodium is another topical anti-inflammatory drug that is safe and effective. Cromolyn often is the drug of choice in children, and topical steroids often are the drugs of choice in adults. These drugs take days to reach full effectiveness and must be taken regularly to maintain the effect. Topical anti-inflammatory drugs are everyday medications, not "bad day" medication.
If the disease is too severe to be controlled by medicines, or if the need to take medications frequently is a problem, allergen immunotherapy injections usually are recommended. Modern materials and methods usually result in major improvement. Since the injections take months to gain control, this is a long-term strategy.
Timothy J. Sullivan is a professor of medicine and the director of the Allergy and Immunology Department in The Emory Clinic. The publication of Wellness is coordinated through the Seretean Center for Health Promotion.