Three major ways of treating allergies are medications, allergy shots and avoiding allergens–substances which produce allergic symptoms.
While each approach is important, there are distinct advantages to allergy shots, which, since 1911, have been used to desensitize people plagued by a variety of environmental allergies.
The major advantage of employing allergy shots is that shots actually reduce or eliminate the allergy. This is not true with medications, which only treat the symptoms.
Furthermore, many allergy medications have side effects such as drowsiness, dry mouth or weight gain not seen with shots. The most common side effects with shots are localized redness or swelling at the site of the shot. Only rarely are there more severe reactions.
Another drawback of allergy medications is that, with time, patients develop tolerance to many of them, decreasing their effectiveness. In contrast, allergy shots improve their effectiveness with time.
Patients who begin allergy shots notice decreased symptoms over 3-6 months, although it make take a year to achieve maximum results.
While relief due to medications is temporary, the decreased sensitivity produced by allergy shots last for years, especially if patients receive periodic maintenance injections.
Thus, while allergy medications provide some symptom relief, these medications are no substitute for the allergy shots, especially in patients with more severe or chronic allergies.
Avoiding allergens such as dust or mold also is helpful, but does not affect the underlying allergy. Moreover, many allergens are so common in the environment that they are difficult to eliminate. Even if allergens are reduced or eliminated in the home, patients may be exposed to harmful substances at work, in the homes of friends or in the outside air.
The use of allergy shots is known as “immunotherapy” –a treatment that actually uses the body’s immune system to reduce allergic sensitivity.
New research results show decreased levels of harmful allergic antibodies, increased levels of protective blocking antibodies, and sensitivity changes in the cells of the immune system following allergy shots.
Patients treated with allergy shots have reduced amounts of chemical mediators, such as leukotrienes or histamine-releasing factors, which cause the symptoms of allergy. Current allergy medications do not work against many of these harmful chemicals.
Allergy shots lead to improvement in both the immediate allergic response, occurring within minutes of exposure to allergens and the late, or delayed, response hours after exposure. Common medications such as antihistamines only treat the immediate response and are not effective preventing delayed reactions.
Controlled scientific studies prove that allergy shots are effective for patients with hayfever (allergic rhinitis), asthma, venom sensitivity and anaphylaxis. Allergy shots may also help some patients with hives, eczema, sinusitis or allergic headaches.
Not every patient requires shots. For example, food allergy or poison ivy sensitivity does not improve with their use. Also, shots are generally not used for infants until or unless their allergies are well-established.
Allergy shots are an important part of the treatment program for many who are allergic. Research continues to improve these shots, but studies over the last two decades have confirmed their clinical and immunologic effectiveness.