Allergic disease is an extremely common and widespread problem with a dramatic increase in incidence in recent years. The National Institute of Allergy and Infectious Disease (NIAID) states that more than 50 million Americans suffer from allergic disease. A recent nationwide survey found that more than half of all US citizens test positive to one or more allergens, such as dust mite, cockroach, grass, or ragweed pollen. allergies are ethe sixth leading cause of chronic disease in the United States, and are responsible for an estimated $18 billion in annual health care costs. In addition, allergic diseases have a significant impact on the quality of life and daily functioning of the sufferer, resulting in substantial indirect costs related to time loss from school or work.
The term “allergy” commonly refers to a hypersensitivity or unusual susceptibility to any offending substance, referred to as an “allergen.” An allergic reaction results when the immune system is provoked into action by exposure to agents such as dust mites, molds, animal dander pollens (grasses, trees, weeds), foods, stinging insect venom, drugs, or chemicals. Symptoms of an allergic reaction vary widely and include “hay fever” (runny nose with itching and sneezing and itchy watery eyes), sinusitis, asthma (cough and wheezing), eczema, hives, gastrointestinal distress, migraine headaches, and most severely, anaphylactic shock and death.
Allergic reactions are mediated by antibodies termed “IgE,” which circulate in the serum and bind to certain blood cells called “mast cells,” which contain the chemicals, most notably histamine, which produce allergy symptoms. An allergic reaction occurs when an allergen reacts with the cell-bound IgE antibody, forming a complex which destroys the mast cell, thus liberationg the chemicals which cause the allergy symptoms.
Traditional allergy therapy includes environmental control measures and an ever-expanding armamentarium of pharmacologic agents (both prescription and OverTheCounter.)
Allergy immunotherapy is employed in patients with problematic allergic conditoins in whom environmental and pharmacologic interventions have been less than successful. The process of preventing allergic reactions through immunotherapy is commonly referred to as “desensitization,” but more correctly referred to as “hyposensitization.” Immunotherapy has been shown to be one of the few therapeutic modalities currently available which can actually alter the course of allergic disease, and it can also provide prolonged relief, which may persist for years after discontinuation of the treatment. It has been shown to be effective in allergic rhinitis, allergic asthma, and hymenoptera (insect venom) hypersinsitivity. Immunotherapy has been shown to decrease the risk of developing asthma when used in children with allergic rhinitis, and to decreas the risk of becoming sensitized to new aeroallergens.
Allergy immunotherapy is traditionally administered in the form of “allergy shots,” which involves injecting over time increasing doses of a vaccine prepared from the purrified proteins of allergens to which the patient has been shown to be sensitive by skin or in vitro allergy testing, followed by maintenance doses of the highest concentrations of extracts tolerated by the patient that relieve symptoms without producing undesirable local or general reactions. The mechanism(s) by which immunotherapy attenuates the allergic response is not entirely clear, but it has been shown that there is both a decrease in production of allergen-specific IgE levels to the administered allergen over time, as well as increased production of allergen-specific IgG, theh so-called “blocking antibody,” which appears to inhibit binding of IgE to the mast cells, thus preventing the release of allergy symptom-causing chemicals.
Though somewhat useful in the treatment of allergic conditions, allergy shots (also referred to as subcutaneous immunotherapy, or SCIT) contain important negative aspects and limits of use. They are uncomfortable and avoided by needle-averse patients. They are inconvenient and time-consuming, requiring weekly office visits and 20-30 minute observation after each injection. They are effective in only 35 – 50% of patients, and allergy symptoms do not improve to the same degree for everyone who uses them. They are more effective for certain classes of allergens than others, and experts do not know how long allergy shots are effective after they are discontinued. Most importantly, there is always a risk of adverse reaction to injection of allergens, either local (at the injection site) or systemic, which may be life threatening (anaphylaxis). Allergy shots are not recommended for persons with coronary artery disease or severe asthma, pregnant women, and children under five. Finally allergy shots are expensive.
Oral immunotherapy, on the other hand, provides a painless,convenient, safe, and effective alternative to injection thereapy. Oral hyposensitization in the form of sublingual immunotherapy, referred to as SLIT, has seen limited usage in this country but is widely used in Europe. Sutdies reegarding its efficacy and safety are currently in progress in both the U.S. and Europe. The problem with sublingual administration of allergens is that the protein antigens are enzymatically degraded and do not reach the immune system intact, thus impeding the proper formation of “blocking antibodies.” In addition many patients have reported uncomfortable itching of the tongue, mouth, and throat.
With these issues in mind, a unique, highly effective method of oral allergy treatment was developed in the 1970’s in Denver, CO, with the invention of a liquid vehicle to which allergy extracts may be added in amounts required for ameliorating allergy symptoms, and which enables the allergens to reach the immune system in their intact, fully potent immunogenic form without enzymatic or acidic degradation during transport through the gastrointestsinal tract. Clinical studies at eleven medical university and clinical centers in the 1980’s demonstrated 92% efficacy with minimal side effects or adverse reactions utilizing this methos of oral immunotherapy.
In summary, oral allergy immunotherapy utilizing a potency-enhancing liquid vehicle is painless, convenient, effective, safe, and economical, and can offer the relief that millions of allergy sufferers have been waiting for!