Allergy Treatment Options
Immunotherapy is a treatment used to reduce or eliminate allergy symptoms by inducing a tolerance to an offending allergen.
There are several ways to administer immunotherapy such as subcutaneous injections, sublingual drops, or sublingual tablets.
Subcutaneous Immunotherapy (SCIT)
Subcutaneous immunotherapy (allergy shots) is FDA approved and is administered with a small needle into the subcutaneous tissue. Allergy shots have been studied and improved for over 100 years. An allergy specialist will formulate these injections by factoring in knowledge of the local aerobiology, patient history, and patient allergy test results in order to create an individualized allergy serum.
Allergy shots are used to treat allergic rhinitis, allergic conjunctivitis, allergic asthma, allergic eczema, and insect-venom hypersensitivity. Allergy shots have the potential to prevent the development of asthma in patients with respiratory allergy.
Research has shown that allergy shots are 85-90% effective in patients with respiratory allergy and 95% effective in those with insect-sting anaphylaxis.
Allergy shots can be administered using multiple allergens at the same time making it beneficial for patients with multiple allergen sensitivities. In the Austin area allergy seasons tend to overlap exposing patients to many different allergens concomitantly.
Patients will receive a shot using a small needle 1-3 times per week during a build-up phase. After building up to a maintenance dose the patient will come into the clinic monthly for their allergy shot. Patients stay on maintenance allergy shot treatment for 3-5 years at a minimum. Patients must wait 30 minutes after injection for an observation period.
Cost is often covered by insurance and many patients experience savings from a decrease in the use of allergy medications, down time at work, and improved quality of life.
Allergy shots can cause local reactions such as swelling and itching at the injection site. Systemic allergic reactions can occur but are rare and usually mild.
Sublingual Immunotherapy (SLIT)
Sublingual immunotherapy (allergy drops) is not FDA approved. The substance in which allergy drops are formulated is FDA approved but not the route of administration. Clinical trials looking at the formulation, dose, and duration of treatment are ongoing in the United States.
Allergy drops were studied as an alternate approach to shots since they can be self-administered and do not require an injection. They are also used to treat allergic rhinitis and allergic asthma.
Allergy drops have been found to be an effective treatment for allergies within certain patient populations. Patients that may benefit from allergy drops are sensitized to a single allergen such as dust mites, cat dander, birch, and grass pollen.
Allergy drops may be administered at home. Allergy drops must be mixed at a concentration that can be 100 times higher than allergy shots due to route of administration. Since allergy drops are not FDA approved there is no professional standards set for effective dose, treatment schedule, or duration of treatment. The lack of guidelines regarding allergy drops leads to a great variation in both preparation and dosing. Allergy drops are proven to only be effective at very large doses. If not mixed this way, patients may receive treatment no more effective than receiving a placebo.
Allergy drops are placed under the tongue 3 times daily for several minutes and then swallowed. This process must be repeated for each allergen on a daily basis. Patient will not get full benefit of drops unless they are compliant with daily dosing. The first dose of allergy drops must be given under physician supervision with a 30 minute in office observation.
At this time allergy drops are considered to be investigational and are not considered standard of treatment. Insurance companies will not cover the cost of allergy drops. A cost benefits analysis has not been determined due the need for more studies pertaining to effective dosing, treatment schedule, and duration.
Allergy drops are relatively safe with the most common side effects including itching of mouth and tongue, swelling of mouth and lips, sneezing, sore throat, nausea, and diarrhea. A systemic allergic reaction has occurred several times during this treatment method.
Sublingual Tablet Immunotherapy (STIT)
Sublingual tablets are FDA approved in the treatment of allergies to Timothy grass and Ragweed.
Sublingual tablets are used to treat allergic rhinitis caused by Ragweed and Timothy grass allergies in patients age 18-65.
Extensive research and development has proven this oral allergen preparation to be beneficial to patients with a single allergy to Timothy grass or Ragweed.
Sublingual tablets are self-administered by placing the tablet under your tongue for several minutes each day. This process must start four months prior to grass pollen season. The first dose must be given under physician supervision with a 30 minute observation. Sublingual tablets must be given in high doses to be effective. The concentration is usually 100 times that of subcutaneous doses.
Although tablets are FDA approved insurance companies are not yet covering them. The tablets cost roughly $10 each or $300 for a month supply.
The most common side effects are itching of ears, mouth, throat, and swelling of mouth and tongue. Rarely, anaphylaxis can occur.
Subcutaneous vs Sublingual Immunotherapy
Shots vs Drops
|Method of Administration||Injection into arm using small needle. Initially 1-3 times/week with frequency being reduced to monthly after “build-up” phase. Administered in physician office with a 30 minute post injection observation period.||Liquid is placed under tongue three times a day and held there for several minutes, then swallowed. May be administered at home.|
|Benefits||Reduces allergy and asthma symptoms in 85-90% of patients.|
May prevent development of asthma in some patients.
|Patients with a single allergen benefit. Not as effective in patients allergic to multiple allergens. Only a few studies have compared these two methods.|
|Yes, both the allergy mixture and method of administration.||No, the allergy mixture is the same but no standard has been set for preparation, concentration, dosing or schedule, therefore it is considered investigational.|
Duration of Treatment
|Patient will receive monthly injections for 3-5 years||Patient will administer daily drops for 3-5 years for best results, although research is still needed to prove the best duration and dosing|
|Local reactions at injection site|
Although rare anaphylaxis can occur
|Itching of mouth, tongue, and ears|
Swelling of mouth and tongue
Gastrointestinal symptoms such as nausea/vomiting/diarrhea
Rare anaphylaxis can occur
|Well defined long term tolerance upon completion of immunotherapy.||Conflicting data, tolerance upon completion unknown. Loss of tolerance upon completing immunotherapy commonly seen.|