Allergen injections are a form of immunotherapy, a treatment based on the concept that if a person's body is exposed to what it's allergic to in small amounts, it will eventually build up a tolerance to the allergen. When over-the-counter and prescription medications offer little or no help to someone suffering moderate to severe allergies, a doctor may recommend immunotherapy.
Common Allergens
Common allergens include pet dander, mold, pollen and dust. Trees, grass flowers and weeds produce pollen. Most plants pollinate at night, making allergy symptoms more severe between dusk and dawn. Dusting a house every day will ease the problem but will never completely eliminate it. Most people who are allergic to cats and dogs are advised not to have them as pets and to avoid coming into contact with them.
Testing
Before a physician begins any treatment, including immunotherapy, he will perform tests. In the case of allergies, a skin test is usually recommended. A tiny amount of allergen is placed on a scratch in the skin or is injected directly under the skin. Usually the scratches are on the back or an arm. After several minutes, the scratches are checked for redness, swelling or other signs of allergic reaction. The amount of irritation will determine the severity of the allergic reaction. Blood tests may also be performed to check for histimine levels, according to MayoClinic.com.
Time Frame
Most people receive shots once or twice a week at the beginning of their treatment program, FamilyDoctor.org explains. The amount of allergen in each injection is gradually increased during this time. It usually takes three to seven months to reach maintenance level. Patients receive allergy shots year-round. Those who suffer severe allergies may need more frequent injections in spring and summer.
Side Effects
Because the serum used in the allergy shot contains the allergen, there may be some irritation at the injection site. Redness, swelling and itching are possible reactions. Allergy symptoms may also appear as the body begins to adapt to the presence of the allergens. Sneezing, a runny nose and watery eyes may be possible.
After receiving allergy shots, the patient must remain in the physician's office to make sure there will be no adverse reactions. A nurse or assistant will check the injection the site for any signs of irritation or reaction before the patient is allowed to leave. This takes approximately 20 minutes.
In severe cases, anaphylactic shock may occur within the first few minutes. Anaphylactic shock is a swelling or tightening of the air passages that may result in the patient not being able to breathe.
Results
Immunotherapy can increase the function of the pulmonary system. It may also reduce the need for over-the-counter allergy medications. In addition, it can alleviate symptoms that may trigger asthma attacks caused by severe allergies. According to the American College of Allergy, Asthma & Immunology, the need for allergy shots may decrease three to five years after a patient reaches a maintenance dosage.
