Allergy Shots or Drops

Great article by Dr. Michael Manning, M.D.

What are the treatment options for documented allergic disease?  If you do not know what the facts are, the answers can be very confusing.  When treating hay fever or allergic rhinitis, asthma and sometimes eczema, there are three main categories of treatment options.  First, one should always try and avoid any offending allergy triggers.  Second, there are a variety of medications that may be effective.  Lastly, allergen immunotherapy, also known as allergy shots, can be instituted if the first two options are ineffective.  So where does allergy drops fit in, if at all?

Allergy drops, or more properly known as sublingual immunotherapy (SLIT), are a form of allergen immunotherapy developed in Europe.  The purpose of sublingual immunotherapy is the same as traditional subcutaneous immunotherapy (SCIT) or allergy shots.  Subcutaneous immunotherapy works by readjusting or rebalancing the immune system so that it stops reacting to allergy triggers.

 When someone is allergic his or her immune system has made an allergic antibody to a pollen, dander or mold.  This antibody, when exposed to the allergen, starts a reaction that ends with the symptoms of hay fever or asthma, such as runny nose, nasal congestion, and watery itchy eyes, coughing or wheezing.  This is actually an over-active immune system.  Therefore the goal of subcutaneous immunotherapy is to calm down this over-active immune response.  For allergy shots to work, the patient needs to be allergic to substances that are appropriate for allergen immunotherapy.  The allergy shot serum should include the allergens the patient is allergic to and not include the ones that they are not reactive to.  This means the serum should be customized to each patient.  Also, the serum must be mixed correctly in that certain allergens cannot be put together in the same serum as they degrade each other.  This process takes time but is the best long-term solution to control allergies.

 Sublingual immunotherapy has the same biological effects as subcutaneous immunotherapy.  This was refined in Europe and has shown excellent benefit when used in the appropriate patient.  Sublingual immunotherapy works best in those individuals that are not allergic to a lot of different allergens.  Currently there are no FDA approved sublingual extracts or serum in the United States. This also means that insurance companies will not cover sublingual immunotherapy. Studies to obtain FDA approval are ongoing.  When FDA approval is obtained, sublingual immunotherapy will be an appropriate treatment option for the control of allergic rhinitis or hay fever and asthma.

 So what is the problem?  Unfortunately, there is a lot of misinformation about sublingual immunotherapy.  Many practitioners advertise drops as being safe with no potential for systemic or severe reactions like can be seen with subcutaneous immunotherapy.  This is not true.  Systemic reactions can occur with sublingual treatment therefore care must be taken when sublingual immunotherapy is started and advanced. Local reactions in the mouth, throat and stomach also occur. Sublingual immunotherapy, when it obtains FDA approval, needs to be performed under proper supervision by a physician specifically trained in allergy and immunology.  Also, like subcutaneous immunotherapy, sublingual extracts should be customized for the patient.  There is no one drop fits all.

 When sublingual immunotherapy receives FDA approval, it will be an added treatment option for patients with allergic rhinitis or asthma.  If avoidance measures and medications do not adequately control symptoms and the patient is only allergic to a few allergens, then sublingual immunotherapy may be the next step in treatment.  In patients who fail to respond to sublingual immunotherapy or who react to a multitude of allergens, then traditional subcutaneous immunotherapy would be the best option.  Until that point, make sure your treatment program is appropriate and backed by scientific study.