Update: Thank you everyone for participating in our AMA so far. Dr. Carr was a bit overwhelmed by the tremendous amount of love and attention the field of Allergies and Asthma was able to achieve with our AMA, but he had plenty of fun all the same. (You should have seen the smile on his face!) I hope you all consider seeing an allergist and starting on the path of treatment/answers. Every day in our office is like a personal AMA session with each patient, so it's always fun. If you're in the area (although we see patients to all over the country and world, as well), we would be happy to meet you. If you mention our Reddit AMA, we'll be even more giddy. Dr.Carr, Audi, and I (OITKristina) will answer questions for one more day (01/25/2020) as we feel that most of the questions have been answered somewhere in the AMA.


Hello, Reddit! I am Dr. Warner Carr, the lead physician for our Food Allergy Center at Allergy and Asthma Associates of Southern California. We help our patients with food allergies by desensitizing them using a treatment called oral immunotherapy (OIT). We are also one of the leading research sites for various food allergy treatments to a variety of foods. Here is a paper I was recently a part of: AR101 Oral Immunotherapy for Peanut Allergy

So, what is the deal with food allergies anyway? It’s so common now that you likely have a friend or even a family member with food allergies. In fact, an average of two kids in every classroom has a life-threatening food allergy. I’m here to clear up the misconceptions about food allergy, discuss current recommendations for food allergy, and answer any other questions in the field that you may have! For example, a common question we get is: what is the difference between food allergy and food sensitivities/intolerance? Food allergies have been controlling people’s lives. It’s time we take back that control.

I am a board-certified Allergy, Asthma, and Immunologist and would be happy to answer any questions about general allergies, asthma, and any other immunological conditions as well. I like to call allergy the “Rodney Dangerfield” of medical diseases because we “don’t get no respect.” Some countries don’t even have allergists. Let’s spread awareness about our specialty!

The Mug Shot (Proof): Dr.Carr and Audi

Our Practice: Our Website, Instagram, Facebook

OIT FAQs: Frequently Asked Questions

All the Participants: /u/WarnerCarrMD, /u/OITAudi, /u/OITKristina

Hello everyone, hope you enjoy our AMA and come to know allergy, asthma, and immunology just a little bit better. We love to share our passion for the subject here! Thank you to r/Allergies and r/FoodAllergies for your support! A few people will be helping to answer questions/type out the doctor’s responses. (- OITKristina)

We will be active 01/20/20 - 01/25/20 from 8:00 AM - 5:00 PM PST. (between patients)

Myself or my scribe (OITKristina) will be answering/transcribing questions.

Comments: 1466 • Responses: 38  • Date: 

CappinPeanut529 karma

Do we have any idea what causes someone to develop a severe allergy? My sister is allergic to tree nuts, for example, but she developed that allergy when she was 18 or so. When I have children, are there steps I can take to prevent the development of allergies, or is it just something that happens?

WarnerCarrMD494 karma

You can develop a new food allergy at any time. Early introduction of the highly allergic foods is the best prevention. If there is a high risk family member then always consider consultation with an Allergist. Each patient is different so that may be helpful.

kindofimpossible321 karma

I have a severe peanut allergy and people always ask me if it’s airborne. I don’t know how to answer this question. I know my allergy is not only from eating the food because I’ve had reactions when I haven’t eaten anything (I assume this was from touching something that someone had touched after eating peanuts or something). I guess my question is, how do I know if my reaction is airborne without testing it (I don’t want to purposefully have a reaction)?

WarnerCarrMD375 karma

Rarely is peanut allergy airborne. It is possible if there is a lot of peanut flour or something like that in the air. However, from the nut itself it is unlikely. You have to have contact or ingest it. Hope that helps.

frizbplaya226 karma

What's your take on non-celiac gluten sensitivity?

WarnerCarrMD242 karma

This is a difficult one. It just depends on what the symptoms are. People can have reactions to foods that are non-allergic. Basically if gluten makes you feel sick then don't eat it. It is unlikely that you will have a severe reaction like anaphylaxis so you will not need an epipen. I usually recommend to avoid highly processed forms of wheat and gluten anyway. Hope that helps.

sarcasticjackass201191 karma

What are the misconceptions about food allergies?

WarnerCarrMD478 karma

The biggest misconception has to do with food intolerance vs. food allergy. The immunologic mechanisms are totally different. Real food allergy can be life threatening because it is mediated by the allergic antibody IGE. This is why we give the epinephrine injectors to people with food allergy. A food intolerance may make you feel bad but it usually does not increase your risk of death. There are lots of others but this is the most common I would say.

Isolatedbamafan137 karma

Have you ever seen an instance of oral allergy syndrome evolving into a more severe allergy?

WarnerCarrMD169 karma

Here is a paper that I wrote on Oral Allergy Syndrome a few years ago. This typically occurs in patients that have pollen allergy. I have seen cases of more severe OAS reactions but usually if you treat the pollen allergy you can treat the OAS. Best treatments would be to first avoid the food and then start allergy shots to the pollen. In the long run it could totally treat the OAS. The risk of anaphylaxis with OAS is low but still higher than the general population. Hope that helps.

foreverisclever112 karma

Do you have any recommendations for parents that will help with children allergies? Does exposure at an early age help?

I am not yet a parent but I have heard that introducing one type of food to children slowly will help identify an allergy. I have also heard that withholding foods - such as peanuts - could be a factor in what can cause severe peanut allergies. This is just from family and friends - is there any truth to either?

WarnerCarrMD121 karma

This is something lots of people have been asking about. In general early introduction of the highly allergic foods is best and can prevent food allergy in certain patients. Hope that helps.

Amperage21105 karma

My mother has a relatively bad soy allergy. Hives, throat closing, etc. None of her doctors have ever seen a soy allergy and new doctors simply don't believe her until she shows up with symptoms after they expose her. How often have you seen soy allergies and given how much soy is in everything from food, clothes, packaging, medical supplies (she had a very severe reaction to medical tape), etc would immunotherapy be a viable option down the road?

WarnerCarrMD206 karma

I see soy allergy all the time. It is one of the most common food allergies. There are specific requirements through the Federal government (US) for food allergy labeling because it's so common. This is one of the foods that I can desensitize people to through the process of food allergy immunotherapy (OIT). We have had great success with our patients.

marvellous-breadfish60 karma

Is there a way to treat food intolerances/sensitivities that aren't allergies?

WarnerCarrMD64 karma

This is a hard one. It just depends on the food and the reaction. In general the safest thing is avoidance. However, some kids may out grow the reaction. Under the supervision of a Food Allergist there may be a time when they should undergo a graded food challenge.

Ozzyandlola52 karma

How often are your patients developing EOE as a consequence of OIT? My youngest son has a plethora of food allergies (IgE-mediated to eggs, milk, peanuts, cashews, pistachios, banana, avocado; FPIES to chicken, oat, and pear). He has been hospitalized 4 times due to severe reactions. He’s only 2 years old, so he doesn’t entirely understand his allergies and can’t be trusted to not eat his many allergens. Our family’s life has been significantly affected by this (I had to stop working since we’ve been unable to find a daycare that can keep him safe; we can not eat in restaurants; travel is VERY difficult; many social and family events are difficult and risky). His allergist is not sold on OIT, though, and keeps telling us how the risks are too high (anaphylaxis, EOE, etc.)

OITKristina34 karma

Hello, it's OITKristina here. I can go ahead and answer this one, as I did most of the data analysis for our clinic patients. The doctor can chime in as well. We conducted an analysis of our OIT Peanut patients from July 2016 to July 2019 for peanut allergy. Of ~250 patients, 1 patient (0.42%) had a confirmed diagnosis of EOE after biopsy. It's still unclear whether the patient would have developed EOE without OIT, if OIT hastened the development of EOE, or if OIT caused him to develop EOE. Regardless, it's relatively rare.

EDIT: Typo

WarnerCarrMD30 karma

EOE was an early concern for OIT, and yes patients can and do get EOE from OIT but the incidence if quite low. Much lower that we thought it would have been. Most reactions to OIT are mild and can be dealt with by and experienced Food Allergist like myself. I have published on the matter in both a NEJM manuscript and a recent abstract30917-2/pdf) published at our national meeting. These two papers look at both the efficacy as well as the safety of OIT. In general it is safe but should ONLY be done by someone that has experience. We should see the first FDA approved product for peanut OIT very soon.

Gr8IdeaPoorExecution45 karma

I was diagnosed with an intolerance for wheat, soy and corn. When I eat them I get an itchy rash on my body and bloat. Additionally, my scalp itches really bad. Despite this, I still crave popcorn and bread. Why would my body be craving what makes me sick? Can you recommend alternatives?

WarnerCarrMD55 karma

You crave popcorn because it tastes good. Many people will have an aversion to the food that causes them a problem but that is not the norm. Just like a diabetic craves sweets even thought it will make them worse. It will take active avoidance on your part. It seems like you are not at risk for anaphylaxis so it you do happen to slip you won't be at risk of death. You will just feel sick.

moss-agate42 karma

I've heard that one of the causes for a rise in allergy diagnoses is that it's more likely that people will survive their first anaphylactic episode or recognise the symptoms of an allergy compared with the past (for instance, a number of historical diaries make reference to certain foods "disagreeing" with the writer, like oysters or marzipan). do you think is accurate or not so much?

WarnerCarrMD64 karma

This is a hard one. Most anaphylaxis episodes don't result in death. However, there are several people who die every year from anaphylaxis so it is not something to mess around with and should be treated immediately with epinephrine. The rise in allergic diseases far out pace the incidence of anaphylaxis so I would suggest this has little impact on the overall rise in allergies.

EmDashxx30 karma

I have two questions!

  1. Can people be allergic to food and only get a symptom like a stomach ache/nausea?
  2. As someone who suffers from debilitating environmental allergies -- do any of these food allergy treatments translate to other allergic reactions as well? I am on shots and the typical meds, but I still get some pretty severe reactions from spring-fall. It's just a hope that someone is working on making my life less miserable, lol.

WarnerCarrMD26 karma

  1. Yes, however it could get worse over time.
  2. There is a lot of research going on right now. The shots can help with some of the food reactions and then we can do OIT if the remaining foods are still IgE (allergic) mediated. Hope that helps.

lsc42729 karma

Hi! I’m getting ready to see an allergist in real life, but I wanted to ask this here as well. I have excessive vomiting when I eat certain types of fish. The culprits have been canned tuna and surimi - I’m afraid to try anything else. Does this sound like an allergy (I don’t have anaphylaxis symptoms), and if so, could immunotherapy help me? I would like to be able to eat fish for health reasons. Thanks for doing this AMA!

WarnerCarrMD56 karma

Vomiting can be a common symptom of food allergy. You are doing the right thing by seeking help from a board certified allergist. At the moment we don't have immunotherapy for fish but we are doing lots of research on. We have active studies going on now. See the Allergist and see if you have fish allergy first. If you do then have a look at this link, which is clinicaltrials.gov. On this site you can have a look to see if there are any investigators doing the studies for fish in your area. Right now there are no studies open but keep checking back. We will be starting a new study on fish later this year. I have been review the protocols.

echo-kierkegaard24 karma

As someone who not only suffers from many food allergies such as seafood, dairy, and various fruits, but other allergies such as pollen, dust mites etc...I have had immunotherapy shots in the past for a total amount of about 3 years.

I stopped taking them after those 3 years. I discovered after by chance that I was no longer allergic to strawberries, which I was previously allergic to. I even had some this morning without any allergic reactions. But I’m still allergic to many fruits so it’s never really made sense to me.

How do you think this phenomenon happened? Does food allergy immunotherapy guarantee somehow less allergic reactions to the allergens or can possibly eliminate the allergy all together if done for a certain amount of years?

WarnerCarrMD19 karma

Both the dose and duration of immunotherapy are very important. Some of your food reactions may be oral allergy syndrome. By doing the allergy shots that can help with those foods. However, if it is classic food allergy you will need to avoid or consider OIT. Three years of allergy shots is the minimum. Many patients need more than 3 years. Hope that helps.

Tolmansweet22 karma

Why do some women develop allergies at the time menopause?

WarnerCarrMD35 karma

Changes in hormone levels can be very powerful. Clearly, they were at risk of developing allergist. Looking at the general population, in childhood, allergies are more common in boys. After puberty, they are more common in women.

IDriveMyself22 karma

Are there any proven tips on how to prevent allergies in the first place?

WarnerCarrMD45 karma

When discussing food allergies, the best prevention is to have a wide variety of foods in the diet at a early age. Especially the highly allergic foods. Early introduction can prevent food allergies in certain cases. In large population studies there is definitely less food allergy with early introduction. There is very little data on probiotics, but they don't hurt. I would recommend natural sources from foods as the probiotic. Hope that helps.

focus_rising18 karma

Is there any sort of age-dependency when considering to OIT? Can it be undertaken by anyone regardless of their age, and is it more effective when undertaken at a specific age?

Thanks from /r/FoodAllergies for doing this AMA!

WarnerCarrMD19 karma

I will usually start at age 18 months or older. However, each patient is different and I will look at all aspects of the patient prior to starting OIT. In general we can do OIT to anyone regardless of age. Immunotherapy tends to be more effective in younger patients. However, we have plenty of adults that we have had great results with.

adorablecyborg16 karma

I believe I have developed oral allergies in my adult life. I always thought that kiwifruit just reacted weird with my lips, but as I got older I started to get the same feeling with pineapple. Now it happens with apricots. It basically feels like a rash in my mouth, or like I ate too much Cap'n Crunch and ruined my mouth.

I'm curious to know if your technique would work with this? I don't want to develop more allergies, but I'm worried that I will with the growing number of fruit and seasonal allergies I've been experiencing...

WarnerCarrMD13 karma

This is most likely oral allergy syndrome related across reactivity to pollen. Read this paper. Best treatment is to get allergy skin testing to environmentals and get allergy shots.

heliumneon16 karma

Thanks for doing this!! My son has a severe allergy to tree nuts. My question is about OIT in general. What percentage of patients can't complete it and what are the typical reasons? My people in the public think food allergies are "solved" but it seems like OIT is not easy or a magic bullet for a pretty big fraction of food allergy sufferers.

WarnerCarrMD13 karma

In my center we have over 95% completion rate. When patients can't complete it there is usually another issue like divorced parents or some logistical issues. Rarely is it because of some adverse response to the therapy. When there are reactions they are typically mild. Look at the NEJM paper I loaded up earlier and have a look at the adverse events. Also look at the abstract I loaded up as it was directly related to adverse events. Very low rates. This is a safe therapy in the right hands.

46andtwojustahead14 karma

Have you focused any of your attention on the role of mast cell activation in food allergies?

I am curious because I was primarily allergy free until developing aggressive systemic mastocytosis. Now I have an extremely restricted diet because I have experienced anaphylactic reactions ~30. Most of those were either drug or food induced reactions, and the food reactions I've experienced were to foods I'd eaten safely for 35 years. I'm subscribed to a couple of subreddits pertaining to mast cell disease and disorders and I know I'm not the only one struggling to eat.

WarnerCarrMD9 karma

Systemic mastocytosis is a complex group of diseases that result from inappropriate activation of the mast cell. In systemic mastocytosis, there is usually a mutation in the cKIT gene that results in continuous activation of the mast cell. So this isn't an allergy in the classic sense with the production of IgE, the allergic antibody. With that being said, if you do have allergy to anything, it can be much worse in the setting of mastocytosis, which is why we always test for things like bee allergy in mastocytosis patients so we can treat it. With regards to the foods, this is something you should have testing for with a board certified allergist who has expertise in treating patients with mast cell disease.

atieka13 karma


Thank you so much for doing this AMA. I have an allergy to tree nuts. Peanuts do not cause any issues (from the research I’ve done, this is due to peanuts being in the legume family vs. the nut family?) for me, and I’m fine being around tree nuts, but when I inadvertently consume them, I have a lot of gastrointestinal issues and my throat/mouth itch severely.

I am extremely allergic to walnuts, pecans, cashews, moderately allergic to pine nuts, and have noticed the least reaction (little to none) with almonds and hazelnuts. I did read being allergic to certain groups of tree nuts and less allergic to others is common with this allergy given the protein structures of these groupings- can you confirm this is the case, or is there another reason why my reactions differ across these groups?

I have done both an allergy test with my doctor and a food sensitivity test from one of those at-home testing companies. The allergy test with my doctor looked broadly at multiple food groups, and included black walnuts on the test, which I came back negative for. The at-home test did not return any tree nut sensitivities.

Would you be able to speak to why this allergy doesn’t provide any positive results in these screenings? Is there a reason why my allergies seem to be flying under the radar? I would assume the black walnuts would’ve come back positive on my first screening.

Again, thanks for doing this AMA!

WarnerCarrMD15 karma

Each nut is different and definitely you can have different reactions to different nuts. They are not all the same. Each has it's own natural history. I don't use the at home food sensitivity tests. They have been shown to be very unreliable and misleading. As far as allergy testing from the Allergist it just depends on several variables on why someone has a reaction on the skin or not. The gold standard test is a oral graded food challenge and should only be done with the supervision of a trained allergist. That can give you the final answer on food allergies.

ExtrovertedBookworm13 karma

What are your thoughts on the theory of people being super resistant to the smell of certain foods as a “warning” that they’re allergic to that food?

For example, I’m allergic to tree nuts, and the smell (especially when cooked) makes me nauseous.

I’m also super sensitive to the smell of seafood - like have to run and hold my breath in the grocery store, hate going to restaurants because some might order fish, have to leave the house if someone is cooking it sensitive. Is that just being overly sensitive, or a “warning flag” that I’m allergic and to avoid seafood?

WarnerCarrMD18 karma

Many people that are allergic to foods have an aversion to it - mainly taste. However, I suspect that anything is possible. Sensitivity to the smell of a food is not necessarily a clear indication of an allergy. It is recommended that you see an allergy specialist and they can do the appropriate testing.

ExtrovertedBookworm9 karma

Unrelated to the other question, but equally curious:

Artificial sweeteners (all types, haven’t found one I can have yet) give me SEVERE gastrointestinal issues - think stomach flu. Is this an allergy or an intolerance, and how can I get doctors to take it seriously? I’ve been told that’s not a thing, and they have no code for it in the online patient records system. I’ve had experiences where they don’t look at ingredients in medications I’m prescribed and then I get even sicker than I was in the first place! What can I do?

WarnerCarrMD7 karma

This is most likely an intolerance or digestive issue with regards to digesting the sugars or chemicals used in artificial sweeteners. Best advice is just to avoid them.

figandmelon12 karma

Do you think xolair should be given to anyone who has an anaphylactic history and tests high forba food allergy? Are there any other proven methods to reduce allergic response/reactions?

WarnerCarrMD21 karma

There are current studies going on to look at the use of Xolair in food allergy. This is complex and Xolair is not for everyone. Especially children as we don't know what the long term safety is in this age group. I wrote a paper on Xolair in 2004 that you can read about. It has been used in food allergy for quite some time.

xcmagnar11 karma

Any chance your research provides any pathways or relief for oral allergy syndrome? It started as just carrots, apple skins, and celery when I was ~9 years old, now I can hardly eat any fruit or nut raw without getting a swollen itchy mouth/ throat.

WarnerCarrMD12 karma

Here's a paper on oral allergy syndrome. Best treatment is allergy injections to the pollens that your're allergic to causing the oral allergy syndrome. Over time, this can lessen the symptoms associated with oral allergy syndrome that you are experiencing.

bituna9 karma

When it comes to uncommon allergies (ie oranges) that cause an anaphylactic response in an adult patient, how would you go about treating the allergy?

WarnerCarrMD9 karma

No different than any other food. There are thousands of things that people can be allergic to. The primary therapy is avoidance and to carry a epinephrine injector. There are many foods that we can treat with OIT but oranges are not one of them. I am certain over time we will be able to expand our therapies to less common foods.

SpaghettiSnack8 karma

Hello! Thank you so much for taking the time to do this AMA. I have had a severe anaphylactic dairy allergy my whole life (I’m almost 20 years old), but I sometimes struggle with discerning between an actual reaction and anxiety. For example, if I smell cheese or butter it sometimes creates a sensation similar to a reaction. I’ve never had any real symptoms after smelling an allergen, so there should be no worry, but it sometimes causes a sensation of a dry throat or itching. Is it possible to develop an airborne allergy at my age? Thanks!

WarnerCarrMD7 karma

I totally get your symptoms and hear it a lot from my patients. I call it food anxiety and as I treat the food allergy then I treat the food anxiety. To answer your question it if very unlikely that it is airborne in the form of cheese or butter. That is likely the food anxiety. Milk is something at your age you will likely not outgrow. Continue avoidance but really consider doing OIT. Hope that helps.

peripateticpeople7 karma

My 7 year old has outgrown several allergies but is still affected by gut reactions to dairy (IgE) and wheat(non IgE). We are on the ladder for dairy but what is your recommendation for wheat? Also he was still ana to tree nuts and peanuts at last hospital test but from an accidental exposure, he seems to have improved. There is no OIT in this country; would you suggest seeking it out?

WarnerCarrMD6 karma

Not sure what country you live in but I have several patients who come to see me from other countries for OIT. The non-IgE reactions can be hard. It just depends on what the reaction is and what is the immunological mechanisms at play. To be safe I always recommend to continue avoidance for now. This sounds complex and I can really only say so much in a forum like this. Details is where the critical advise comes in. See an Allergist locally if they have them in your country.

blondebeard2277 karma

How much weight do treatments using parasites (such as hook worms) to treat allergic reactions hold in the medical community? Are they ever truly considered a viable option even in extreme cases?

WarnerCarrMD14 karma

I put no weight in this approach and it could be dangerous. Don't infect yourself or your children with parasites to treat allergies.

Skymimi7 karma

I have developed food sensitivities to all grains, red meat, dairy, strawberries, carrots, eggs, nuts and soy, to name a few. I do best on a diet of veggies, fruit, and chicken, turkey and seafood. I was on allergy injections for over 20 years for inhalants, which I just recently stopped because they weren't making a difference. I have a lot of acid reflux if I don't keep my diet super strict. Could this be associated with gut health? And, why would it? If, not, why would I develop this over time? Any treatments available? Thanks so much for your time.

WarnerCarrMD8 karma

Sounds like your history is complex and the devils would be in the details. I agree that 20 years of allergy shots is not likely going to provide you additional benefit, so I would have stopped them as well. It is unclear what the mechanism is of your symptoms. Make sure you see a GI doctor to make sure you don't have some form of colitis. Beyond that, working with a good nutritionist may be very helpful for you.

imwithadd5 karma

I heard there is a rise in allergies because people were told to avoid known allergic foods as babies, such as peanut butter, and now they recommend introducing allergenic foods sooner. Is that true?

WarnerCarrMD4 karma


Warriorsheir4 karma

How would your office go about treating someone with difficulty digesting complex gluten from GMO wheat and such?

WarnerCarrMD6 karma

This just depends on the symptoms and history. It is more complex than you think. The easiest thing to do is just avoid wheat for now.

larkasaur3 karma

I like to call allergy the “Rodney Dangerfield” of medical diseases because we “don’t get no respect.”

Why do you think this is?

WarnerCarrMD8 karma

I don't know for sure but my suspicion is patients don't have symptoms all the time so they don't think it is a real problem. They only worry when they have active symptoms. That's my thought at least. Also, people who don't have allergies don't really understand the impact it has on those who suffer from allergic diseases.

czarinacat1 karma

I was tested for wheat allergy (negative) and then Celiac disease. My tTG antibody was negative (had been gluten free for about one month prior to testing) but my serum IGA was 495 (reference range is 61-356). My allergist has no idea what an elevated IGA means. Do you know if this is causing my food sensitivities? Currently sensitive to gluten and soy.

WarnerCarrMD3 karma

Individual cases vary, so it's hard to be definitive...on Reddit. However, there is other blood testing that can be done, such as your HLA haplotype, as well as other blood tests for celiac. The gold standard is a biopsy; however, you have to be eating gluten to have a positive biopsy. If your symptoms have resolved while avoiding gluten, just continue to avoid gluten.

CrochetyNurse1 karma

May be a dumb question, but I haven't been able to find an answer and I'd like to be able to give my patients the best info:

Does the increase in immunotherapy for cancer make the risk for food allergies increase, decrease, or not change?

WarnerCarrMD2 karma

Tough question and not sure it has been studied in great detail. In general I would say there is no relation. However, it does depend on the cancer and treatment.