Your body’s immune system typically does a remarkable job protecting you against most foreign invaders, creating antibodies and preventing the negative effects that some substances may cause. An allergic reaction can better be called an overreaction, since your immune system response is out of proportion to the potential harm of the allergen. In fact, in many cases, the allergic reaction itself is a bigger problem than the substance causing the reaction.
When the immune system runs rampant, it can lead to inflammation in your skin, lungs and airways, or digestive system. On top of this, the immune system’s reaction usually isn’t effective on the allergen, so the stimulus remains, your allergy symptoms continue, and only avoidance of the allergen provides relief.
In-office skin testing takes about 15 minutes and gives you immediate results about what you’re allergic to. Drops of various environmental and food allergens are placed on the forearm and the skin is quickly pierced with a tiny lancet. Each allergen is evaluated for localized reactions that indicate an allergy.
Allergen immunotherapy, the formal name for allergy shots, works in a similar way to vaccines. Based on the results of your skin testing, controlled doses of the substances you’re allergic to -- called allergens -- are injected at regular intervals. The concentrations are such that you won’t have a full reaction to the allergens, but your immune system has a chance to recognize and formulate defenses against them. Over time, you become desensitized or develop immunity to the problem substances.
Allergy shots work in two phases. The build-up phase consists of shots once or twice a week, with increasing amounts of allergens, over a period that typically lasts for three to six months. The maintenance phase delivers a consistent dose of allergens once or twice a month.
Response to allergen immunotherapy varies widely from patient to patient. Some people see relief from allergy symptoms almost immediately, while results take longer for others. If you’re benefiting from allergy shots, therapy typically continues for three to five years.
Though not recommended for children under five years of age, allergy shots can be very valuable to the development of a child’s immune system. Left untreated, allergic reactions may develop into medical conditions, such as allergic rhinitis or asthma.
Severe reactions to allergy shots are rare. The most common reactions are redness and soreness at the site of the injection, though it’s usually short-lived, so allergy shots are typically safe for children.