Immunotherapy Allergy Treatment For Peanut Allergies and Beyond

With all of the talk about peanut immunotherapy these days, you'd think that the cure for these life-threatening allergies was right around the corner. While there is no quick fix, immunotherapy in one of the various forms may well be a viable option for treatment of food and environmental allergies.

As my son has acquired more allergies over the years, even with "total avoidance," I've been looking into immunotherapy recently.  Although I'm not a physician, I'll share with you my "lay moms" understanding of some of the different types of immunotherapy.

When a person has allergies of any kind, the immune system behaves as if an innocent substance (pollen, peanut, pet dander) is a threat, and the body's response to this threat can be anything from watery eyes or a runny nose, to anaphylactic shock. Ideally, immunotherapy re-teaches the immune system to become less sensitive to these everyday substances.

There are several kinds of immunotherapy available including subcutaneous immunotherapy, oral immunotherapy, and sublingual immunotherapy. Let's take a brief look at each one.

SCIT is an acronym for subcutaneous allergen immunotherapy.  SCIT is what is commonly referred to as "allergy shots" and is the most common form of desensitization treatment in the U.S.  Specially prepared doses of antigens (the substances you're allergic to) are injected, and the amounts are increased over time until the patient is desensitized. Here in the U.S., allergy shots are used for environmental, seasonal or venom allergies, not for food allergies.

Oral Immunotherapy or OIT has gotten a lot of media attention lately as a potential "cure" for peanut allergy. Oral immunotherapy is done by steadily exposing patients to minute quantities of the allergen (for example, peanut in a carefully prepared powder) over months or even years, gradually increasing the amount of the allergenic substance over time.  Oral immunotherapy is considered a promising treatment for food allergies, although there are serious risks and this treatment should never be tried at home.

SLIT is an acronym for sublingual immunotherapy. This treatment is similar to shots in that the prescribed antigen is given in increasing doses in an effort to desensitize the patient over time.  A major difference is that the allergen extract is given to the patient in drops (or tablets) under the tongue (sublingual means "under the tongue.") This therapy is commonly used in Europe and may be an option for children or those who are needle phobic. Like allergy shots, SLIT often takes three to five years to reach the full effect; however some patients start to benefit from this treatment within a few months. 

Although many of the antigens used for SLIT are FDA approved for allergy shots (SCIT), when used sublingually, this treatment is not yet FDA approved, which means that most insurance companies will not cover the price of the drops. Experts estimate that about twenty percent of all drugs prescribed in the US are "off-label" so it's not uncommon for drugs to be prescribed this way.