I have to take my mind off coronavirus somehow, so I thought I would provide the latest update on our experience with oral immunotherapy for food allergies. 

We’re done for now

We have stopped oral immunotherapy updosing, after having reached a dose of 1 whole nut for each child (see why in the section below, “New information since we started OIT”). So now we are entering maintenance phase at a daily peanut for one child and a daily cashew for the other. Our allergist said that after about 3 months on the 1 nut dose, they would be protected from accidental ingestion of up to 2-3 times their dose – which would be about 2-3 nuts.

Time involved

It took us 7 months, updosing on a schedule target of every 2 weeks, to go from roughly 2.5mg of nut flour to 1 of an actual, decent-sized nut. We had a few updoses with 2.5 to 3 weeks in between due to illness, scheduling availability, and travel. 

We’re only 30 minutes away from our food allergist. Each appointment was 1.5 hours long. I got used to measuring out the nut flours everyday. All in all, in retrospect (now that it’s over!), the time invested didn’t seem so bad.

Reactions during updosing

Overall, we had a pretty smooth experience with updosing. We did not have any anaphylactic reactions. We followed most of the guidelines: 

• We usually dosed in the evenings around 7 to 7:30pm. Our kids go to bed around 9pm. We did occasionally dose late around 8pm.
• We skipped dosing on particularly hectic/exciting days like Halloween.
• We did shower after the dose a few times, but we kept it particularly short and not too hot and did not have reactions.
• We dosed with Zyrtec on updose days and for 2-3 days after based on initial recommendations of our allergist.
• Both my kids had occasional tummy aches, but I could never be certain if it was related to dosing. I suspect that some were and some weren’t. 
• Twice, one child had the feeling of something in the throat. Both resolved with Zyrtec.
• My peanut-allergic child had coughing reactions on 5-6 occasions within the two hour window of dosing that were resolved with Zyrtec. 
• It was recommended that we treat our peanut-allergic child with Qvar or other asthma control medication because there were also environmental allergies that presented with allergy-induced asthma symptoms (periods of recurrent, mild coughing and more coughing symptoms during colds). Ultimately, we stopped the Qvar because of some behavioral changes that accompanied its use. 

New considerations since we started OIT

Our allergist basically recommended that we stop at 1 nut. This is a change in thinking since the time we began OIT last year. Originally, our provider thought that OIT would continue up to about 3-4 nuts. Here are the recent learnings that resulted in the change of their decision:

• Clinically, our provider saw that patients in maintenance were having more reactions at 3-4 nuts versus patients who were doing very well on just 1 nut, while conferring a strong level of protection of up to 3 nuts. (Incidentally, for what it’s worth, I learned that a maintenance dose of 8-10 nuts is around the level of what is considered “free eating.”)
• This supported my own anxiety-inducing findings on Facebook OIT groups where it seemed that many parents shared that their kids were having reactions, even anaphylactic ones on maintenance doses of 3-4 nuts or more. 
• Palforzia, the “drug” containing pre-measured doses of peanut flour will also only go up to 300mg (1 peanut), so this falls in line with what is now considered “safe” and FDA-approved.
• I also came across this 2018 Palforzia aka AR101 study that showed only 67.2% of patients who had been on a maintenance dose of 300mg peanut flour were able to pass an exit challenge of 600mg without dose-limiting symptoms. This made me less comfortable about the 2-3 nut protection level mentioned by our allergist. If you’re data-inclined, here’s the appendix for even more details (including the OIT dose schedule, patient characteristics, etc.) on the study.

Next Steps

All in all, our provider suggested that we stop at one nut for now and reassess in 3 months whether we would like to continue, given the recent findings and after we see how our kids fare on their 1 nut maintenance. Our provider also said that we would need to be completely reaction-free for the next 3 months to even consider updosing to reach 3-4 nuts (which is about 3-4 more updose appointments). 

Our peanut-allergic child with suspected underlying asthma conditions would not be recommended to continue past 1 nut due to the risk associated with the conditions, unless we resumed asthma control medications. We’ll have to think hard about that one because the behavioral changes were very unsettling. 

Our other cashew/pistachio-allergic child could be allowed to continue if there are zero reactions in the next 3 months. However, in that case, we would do a pistachio challenge of some sort. When we began OIT, we were told that desensitizing to cashew results in desensitizing to pistachio (due to the cross-reactivity) in about 80% of the cases. Our allergist now says that this is actually the case in 90%+ of the allergies, and after 3 months on the 1 cashew maintenance dose, they would recommend a challenge of eating 3 pistachios in the clinic to see if my child has desensitized to the pistachio as well (1 cashew = 2.5 pistachios).

In the meantime, I’ve been following the continuing developments linking food allergies to the gut and am hopeful that a cure, not just a treatment is in our future.