Subcutaneous / Sublingual Immunotherapy Treatment
Purpose
The purpose of Immunotherapy is to decrease your sensitivity to allergy-causing substances, so that the exposure to the offending allergen (pollen, mold, dust mites, animal danders, stinging insects, etc.) will result in fewer and less severe symptoms. This does not mean that Immunotherapy is a substitute for avoidance of known allergens or for the use of allergy medications, but rather is a supplement to the treatment of occurring allergens. These alterations may permit you to tolerate exposure to the allergen with fewer symptoms. You in effect, become “immune” to the allergen. The amount of this immunization is different for each person and is, therefore, somewhat unpredictable.
Indications
To qualify for Immunotherapy, there must be documented allergy to substances in the environment that cannot be avoided. Documentation of allergy can be either in the form of a positive skin test or a positive blood test. In addition to demonstratable allergy by one of the above tests. Problems such as hay fever or asthma should occur upon exposure to the suspected allergen, or you may have a history of a severe reaction to an insect sting. Due to the inherent risks of Immunotherapy, avoidance measures and medical management should be attempted first.
Efficacy
Improvement in your symptoms will not be immediate. It usually requires 3-6months before any relief of allergy symptoms is noted, and it may take 6 – 12 months for full benefits to be evident. The majority of allergic patients on subcutaneous Immunotherapy note significant improvement of their symptoms within the first year of maintenance injections. This means that symptoms are reduced, although not always completely eliminated.
Procedure
Allergy injections are usually started at a very low dose. This dosage is gradually increased on a regular basis (1-2 times per week) until a therapeutic dose (often called the “Maintenance Dose”) is reached. The Maintenance Dose will differ from person to person. Injections typically are given once or twice per week while the vaccine dose is being increased (Advancement Phase). This frequency reduces the chance of a reaction and permit’s the Maintenance Dose to be reached within a reasonable amount of time. After the Maintenance Dose is determined, the injections can be given every one to three weeks. Sublingual Immunotherapy is an alternative to allergy injections. Sublingual Drops are administered once a day at home.
Duration of Treatment
It usually takes 3 – 6 months to reach a Maintenance Dose. The time may be longer if there are vaccine reactions or if the injections are not received on a regular basis. For this reason, it is important that the recommended schedule be followed. If you anticipate that regular injections cannot be maintained, Immunotherapy should not be started. Immunotherapy may be discontinued at the discretion of the doctor if the injections are frequently missed, as there is an increased risk of adverse reactions under these circumstances. Most Immunotherapy patients continue treatment for 3 – 5 years, after which the need for continuation is reassessed.
Adverse Reactions
Allergen Immunotherapy is associated with some widely recognized risks. Risk is present because a substance to which you are known to be allergic is being administered to you. Some adverse reactions may be life threatening and may require immediate medical attention. Potential adverse reactions included, but are not limited to, the following (listed in order of increasing severity):
A. Local Reactions
Local reactions are common and are usually restricted to a small area around the site of the injection. However, they may involve the entire upper arm, with varying degrees of redness, swelling, pain, and itching. These reactions are more likely to occur as you reach the higher concentrations and higher volume injections. The reactions may occur as you reach the higher concentrations and higher volume injections. The reactions may occur several hours after the injection. You should notify the injection nurse if your local reaction exceeds one inch in diameter or lasts until the following day.
B. Generalized Reactions:
Generalized reactions occur rarely, but are the most important because of the potential danger of progression to collapse and death if not treated. These reactions may include:
- Urticarial reactions (hives) include varying degrees of rash, swelling and/or itching of more than one part of the body. There may be mild to moderate discomfort, primarily form the itching. This reaction may occur within minutes to hours after an injection.
- Angiodema is rare and is characterized by swelling of any part of the body, inside or out, such as the ears, tongue, lips, throat, intestine, hands or feet, alone or in any combination. There may occasionally be accompanied by an asthma exacerbation and may progress to the most severe reaction, anaphylactic shock. In the absence of shock, the principle danger is in suffocation due to swelling of the airway. Angiodema may occur within minutes after the injection and requires immediate medical attention.
- Anaphylactic shock is the rarest complication, but is a serious event characterized by acute asthma, vascular collapse (low blood pressure), unconsciousness, and potentially death. This reaction is rare and usually occurs within minutes of the injection, however, there are reported cases of anaphylaxis beginning as long as 2 hours after an injection.
The above reactions are unpredictable and may occur within the first dose or after a long series of doses with no previous warning. All generalized reactions require immediate evaluation and medical intervention. If a localized or generalized reaction occurs, the vaccine dosage will be adjusted for subsequent doses. Appropriate advice and treatment will always be available from our office staff at the time of any adverse reaction. As an additional precaution, the doctor recommends that all Immunotherapy patients carry an emergency epinephrine autoinjector with them on the days that receive Immunotherapy.
PREGNANCY
Females of child-bearing potential: If you become pregnant while on Immunotherapy, notify the office staff immediately, so that the doctor can determine an appropriate dosage schedule for the injections during pregnancy. Immunotherapy doses will not be advanced during pregnancy, but may be maintained at a constant level.
New Medications
Please notify the office staff if you start any new prescription medication, particularly for high blood pressure, migraine headaches, and glaucoma.