What is OIT (oral immunotherapy treatment) for Food Allergies?

I first learned of OIT (oral immunotherapy) for food allergies after joining some online groups for parents of food-allergic children.  It is a physician-supervised treatment in which the patient takes small amounts of his or her allergen orally, beginning with minuscule quantities and gradually increasing to larger amounts over time.  It works on the basis that the immune system, which is falsely attacking food proteins as foreign invaders, can be desensitized over time.  In these online groups, I saw pictures and stories of children eating handfuls of peanuts after previously experiencing life-threatening allergic reactions from ingesting invisible amounts of peanut.  

I was intrigued, but scared to say the least.  So far, Sean has never had a severe reaction.  If we just left him alone, perhaps he never would.  The thought of feeding him his allergen seemed a bit like playing with fire.  What if I do more harm than good?  But then I remembered what we've already got stacked against us.  Peanut allergy is the leading food allergy related to anaphylaxis.  For those who don't know, anaphylaxis is a severe, life-threatening allergic reaction.  It can be brought on by exposure to a very small, even invisible, amount of an allergen, and can escalate to death within minutes due to the involvement of multiple major body systems.  Initial symptoms may be complaints of itchy or tingly lips, tongue, or throat.  The sufferer will likely begin sounding hoarse, coughing, wheezing, and have difficulty breathing.  Some experience gastrointestinal symptoms such as abdominal pain and cramping, vomiting, and diarrhea.  Hives may erupt on the skin.  Swelling is likely, and is especially noticeable in the face around the mouth and eyes.  This swelling occurs as fluids leak out of the blood vessels and into body tissues.  As a result, the blood pressure drops and may become dangerously low.  The body will try to compensate for the low blood pressure by increasing the heart rate.  For this reason, people who are experience anaphylaxis are often found with low blood pressure and rapid pulse.  However, in about 10% of cases, the blood pressure and pulse will both be low.  If this condition is not corrected quickly with a medication called epinephrine, either in an emergency department or via auto-injectors such as the Epipen or Auvi-Q, the condition can rapidly lead to unconsciousness and death.

As I read about OIT, I found that about 80% of the patients who begin it are successfully treated.  I decided that sitting around doing nothing was just as scary as all the unknowns associated with OIT, so I made the call to set up the appointment.

Assuming Sean is deemed a good candidate for OIT, we will begin with one long day where he is periodically fed extremely small doses of a peanut solution while his vital signs are constantly monitored and he is watched for signs of a reaction.  A dose will be determined for him to continue at home, and we will continue to dose him on our own (with Epipens in hand, I'm sure) until his next appointment.  We will have to make the 3.5 - 4 hour drive every week or two for a dose increase that will be given in the office.  If tolerated, we'll again be sent home to continue the dosing on our own.  This will happen repeatedly over many months and if all goes well, it will end with him being able to eat multiple whole peanuts.  I can't even imagine that at this point!  Because this is a relatively new treatment and is still considered experimental, there is not a lot of information on how long he will have to continue daily maintenance dosing once the treatment is completed.  It may be that he will have to continue eating peanut products on a daily basis for the rest of his life (or a minimum of several years) to maintain his desensitization.  We'll cross that bridge if and when we get there, and I really, really hope we get there!