For one out of five unlucky souls in the U.S., there’s no mistaking the red, swollen eyes, drippy nose, sore throat and angry, inflamed nasal passages. The average person battles the scourge of allergy season with a small arsenal of pills, drops and inhalers, to the tune of $120 a year. And that’s merely to stifle symptoms. Worse yet, such treatments won’t stop about 20 percent of cases of allergic rhinitis from progressing to full-blown asthma – a condition that, despite improvements in drug therapies, now kills twice as many people in the U.S. every year as it did in 1980.
One weapon to tame the overreacting immune system is immunotherapy – gradual delivery of the substances that trigger allergies to acclimate the body to the world around it. In children it has been proved to prevent the development of new allergies and even asthma. For adults it can reduce the sneezing and wheezing of rhinitis by 80 percent and reduce the need for medications by an impressive 88 percent. This approach, however, requires the patient to assume the role of pincushion–doses must be delivered via a large needle twice weekly for the first few months and then monthly for up to five years. That’s a total of at least 100 shots. No wonder the American College of Allergy, Asthma and Immunology found immunotherapy to be seriously underused.
But immunotherapy may soon be much more patient-friendly, thanks to the renaissance of an idea that has been around since the early 1980s–placing drops of the allergen extracts under patients’ tongues. Mainstream medicine has been slow to embrace the latest incarnation of sub lingual-swallow immunotherapy, or SLIT, but growing evidence from various clinical trials in Europe and a recent endorsement by the World Health Organization have made the idea much more palatable.
David Morris of Allergy Associates in La Crosse, Wis., is the most vocal advocate of SLIT in the U.S. He’s leading an online campaign at allergychoices.com to educate other physicians and patients about the benefits, although skeptics argue he’s no Jonas Salk. When asked to explain how the delicate allergens can survive the harsh environment of the digestive tract long enough to influence the immune system–the most common criticism of oral administration–Morris sighs and says, “I don’t have to explain how it works. I have 60,000 patients who’ve had relief with the drops.”
Luckily, research has begun to validate his campaign. Of 18 double-blind, placebo-controlled clinical trials in the past 15 years, 16 confirmed the effectiveness of SLIT in reducing patients’ reactivity to grass pollen, house dust mites or birch pollen. Thus far studies have found that drops were as effective as shots and, not surprisingly, were better accepted by patients and were safer–though rare, a fatal systemic reaction to the shots is possible. This trickle of scientific support has prompted Richard F. Lockey, director of the Division of Allergy and Immunology at the University of South Florida College of Medicine, to put at least one foot on the SLIT bandwagon. “I’m a very skeptical person, and if I’m starting to believe it works, there might be something to it,” Lockey says.
He concurs with the latest recommendations offered in “Allergic Rhinitis and Its Impact on Asthma,” a position paper published last November for the World Health Organization by an international consortium of 34 allergy experts. The group cautiously backs the use of sub lingual therapy, especially for people who have experienced reactions to injections or who are not likely to comply with a regimen of shots. Immunotherapy “should be a first-line therapy,” Lockey says. “We need the drops, and we need them soon.”
By Brenda Goodman
