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Do pollen allergies cause anxiety?

Feeling anxious?

You’re not alone.

The NY Times ran a story about a year ago titled “Prozac nation is now the United States of Xanax.”

Why is everyone anxious? If you believe, as I do, that anxiety is a symptom, not an identity, there are lots of potential reasons, many of which are work stress related. Constantly checking email for news of a fire drill at work will put anyone in a state of anxiety.

Allergy and mental health

But today I want to focus on a lesser known cause of anxiety, which is seasonal allergies.

When you think of allergy, you probably think of itchy, watery eyes and sneezing, maybe a cough. You don’t think of mental health. But living in an environment with multiple allergy triggers can cause anxiety.

For those of you who regularly read the blog, you know I’ve been writing a lot lately about histamine, a topic that first came on my radar after having a rough allergy season when living in Austin (I have since moved, 100% because the allergies are so severe there for me that I simply cannot live there).

You can read my histamine intolerance post here, but the bottom line is that pollen allergy, or any other seasonal allergy, can cause mental unrest when it’s paired with other factors that cause histamine to build up to excessive levels in the body, or when the allergy is severe enough on its own to cause histamine overload.

In my case, I had some allergy tests done and found that I have some major allergies to central Texas grasses, like Timothy and Bermuda grass. When the grass was in full swing a few months ago, I would wake up feeling unusually scattered and on edge. When I went to California, as I do often, I experienced a total abatement of symptoms.

Total Zen mode, relatively speaking.

This began to fascinate me. Why was I calmer in San Diego?

I’m sure there were a few factors at play, but one was certainly allergy related. There is nothing I am allergic to in San Diego.

The whole experience of living in Texas, and the utter pain the environment visited upon me, was so odd, I felt compelled to write this post for what I imagine is a large group of people who would be better off taking a Zyrtec, or a whole bunch of vitamin C (has been shown to clear histamine), than they would a benzodiazepine.

Allergies can contribute to anxiety

I wouldn’t go as far as to say that pollen allergies cause anxiety. I think it’s more accurate to say that they contribute to anxiety. For most people, normal airborne allergens alone won’t be enough to cause severe anxiety symptoms. It’s likely you’ll need to add to the equation reduced genetic ability to clear histamine, a diet of at least some histamine rich foods, or compromised gut health, so the issue, like most, is multifactorial.

Having said that, if any one of the following four factors are particularly strong, that factor alone could be causing your anxiety.

  • Allergens12
  • Histamine Genes
  • Compromised gut health plus histamine rich food

Let me explain.

Histamine affects the central nervous system

People forget that histamine, the stuff your immune cells release when they perceive a threat (and if you have allergies, pollen is a threat), is a neurotransmitter.

It is responsible for cell to cell communication, sending signals that impact sleep, body temperature, cardiovascular signals, food intake, memory and much more.3

Simply put, histamine affects the central nervous system and anxiety is one of the tell tale symptoms of histamine intolerance. The equation is relatively simple: as histamine levels rise beyond what your body can effectively clear, symptoms like anxiety can rear their ugly head.

The histamine genes

We screen for both of these genes as part of assigning a histamine score to our custom nutrition plan customers.


The terminating enzyme for histamine clearance is called histamine-N-methyltransferase and its job is to clear intracellular histamine as well as histamine in the brain.4 Not everyone has the same ability to clear histamine. HNMT levels can vary by as much as 5 times between individuals based on genetics.56


Diamine oxidase (DAO) is another enzyme I’ve written about lately. DAO is found in largest concentrations in the gut and its job is to clear extracellular, or free floating histamine. Like HNMT, variants in the AOC1 gene (the gene that is coded to make DAO) have been associated with varying levels of DAO. Lifestyle decisions can also reduce DAO. NSAIDs, antibiotics, and alcohol are some of the biggest culprits for reducing DAO levels.

If you have reduced genetic ability to clear histamine, or you’ve recently taken high dose Ibuprofen or a potent antibiotic, and you live in an environment with multiple allergy triggers, you could be predisposed to anxiety, especially while on a histamine rich diet, and especially during allergy season.

My experience with pollen and anxiety

I eluded to this above, but my personal experience is that I feel calmer in coastal cities, especially in California (kind of hard to go into Zen mode in NYC). I don’t have many HNMT SNPs but I do have a relevant AOC1 SNP which is associated with reduced diamine oxidase levels, the enzyme that clears histamine from the gut, and the Texas grass is what seemed to push me into symptom range all on its own.

Note: I have never had my serum diamine oxidase levels tested. My understanding is that it is difficult to find good labs to run this test – which doesn’t mean there aren’t labs that can run a DAO panel, just that it may be tricky to get reliable results.

Note: While most blogs exclusively discuss DAO and HNMT in connection with histamine intolerance, AOC1 and HNMT are not the only genes that affect histamine metabolism. We also include IL-8 and ALDH2 as part of our histamine scoring system.

During spring time, removing myself from environments where severe allergens are present in large amounts, like Austin for example, improves my quality of life.

See also: Why are my allergies so bad in Austin?

Studies linking allergy to anxiety

Think this is all bullshit?

Consider this meta-analysis of studies done on allergy and anxiety /depression that appeared in the Journal of Innovations in Clinical Neuroscience:

Through a review of the relevant articles in the PubMed and PsycINFO databases, the authors found that the majority of studies (9 of 11 studies on anxiety syndromes, 10 of 12 studies on depressive syndromes) indicate associations between allergies and anxiety/mood syndromes, despite a number of methodological variances.

Interestingly, one of the studies included in the meta-analysis found a link between self reported hay fever and panic attacks.7 At first glance, it seems strange, but once you start thinking of histamine as a neurotransmitter that impacts the central nervous system, which it is, it all starts to make sense.

Do you have allergies and anxiety?

Removing yourself from an environment with loads and loads of airborne allergens, or popping some Zyrtec, could be better than Xanax.

Experiments to run:

All subject to the approval of your physician.

  • Zyrtec (start with the lowest possible dose so you can find the minimum effective dose)
  • Try a low histamine diet to see how you feel
  • Try a grain free diet and see how you feel (grains could be creating an environment in your gut that causes bacteria to flourish that produce histamine)
  • Go to the coast for a few days, see how you feel
  • If you haven’t already, find out what you’re allergic to in your area through traditional allergy testing
  • Get your genetic data and check for histamine clearing SNPs

Key takeaways

There is abundant scientific evidence establishing a link between mental health and allergy. so if this is something you are experiencing don’t let someone talk you out of a hard fought insight.

The health and wellness world loves to identify all the foods that can cause inflammation in people, but there is very little attention paid to the myriad ways our ambient air can be a driver of inflammation as well.

John O'Connor

John O'Connor is the founder of Gene Food, a nutrigenomic startup helping people all over the world personalize nutrition. John is the host of the Gene Food Podcast and a health coach trained at Duke's Integrative Medicine Program. Read his full bio here.

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  1. Ch says:

    San Diego happens to be (I forget where I read that) the place with the most stable climate in the US. In the same time when pollen allergies arise, the weather becomes unsettled. For me, that is the main driver of my anxiety. Hands down. So going to San Diego in spring would dissipate my anxiety, too.

  2. Megan M says:

    What consumer companies test your DNA for the HNMT and AOC SNPs? I haven’t found one yet, since they are mostly focused on ancestry…or do you have to get a complete genome sequence done? Is there any info or evidence for a difference in treatment if it’s an HNMT vs DAO issue? I’ve been on a low histamine diet and doing more meditation which has been helpful but wondering how far down the rabbit hole to go

  3. Mary K. says:

    It would be helpful to mention Mast Cell Activation Syndrome in your posts to build awareness for patients with chronic Histamine Intolerance. Treatments include a low Histamine diet, mast cell stabilizers, antihistamines and/or Xolair. For those who cannot tolerate medications, compounding is available.

    • Mary K. says:

      Additionally, mast cell activation is comorbid with Ehlers-Danlos Syndrome (hypermobility) and POTS.

  4. Lara says:

    Thank you! I have been so frustrated because anxiety symptoms keep coming back and it makes me feel like I can’t handle an ounce of stress. I noticed last year in April it was our anniversary, which should have been a joyous time, was an anxious time! This April I feel the same symptoms. Thank you so much for this article!

  5. CeCe says:

    I was hit with brain fog in later 2014. March or April of 2015 sent me to the emergency room with rapid heartbeat, and extreme dizziness, anxiety, and near fainting. Repeat for 5 years. They did MRIs CT scan, all came back normal. But my feelings of dizziness and anxiety kept coming. I also bruised easy due to not eating well and low d3. Well, started eating right and bruising cleared up, but randomly the symptoms would appear. Well fast forward to rihht now. Spent hours on my social media back combing my posts. My symptoms seemed to show up Late Feb up to about August……POLLEN SEASON, noticed my sinus burned like hell during the day of that time, and my nose clogged bad at night. All these damn doctor and er visits and no one thought hey maybe its alletgies. I started my first Claritin dose today. I will be pissed (constant misdiagnoses by professionals) yet relieved if it happens to get me through the day without head pressure, and vertigo.

    • Stephanie says:

      So glad I found this article and reading everyone’s symptoms! I lived in Georgia for 4 years than moved to Louisiana came back after 4 years and pollen season starts and bam! Allergies are so bad I feel like I can’t breath. That turned into having major panic and anxiety attacks. Some days are better than others. I’m thinking it has to be related I’ve never had anxiety in my entire life and now dealing with sever episodes. Makes me think about moving back to Florida where I grew up and was fine.

  6. Sherrie says:

    Thank you for posting this! I first noticed issues with my daughter when she was in Kindergarten. Her birthday is in February and annual check ups were always positive. By March/April, she would become very forgetful, anxious, irritable. I didn’t pick up on the pattern until second grade and brought to doctor’s attention. Nope, they didn’t think that was it. Every year I would mention it to them. The period of ‘anxiety’ would last for about 6-8 weeks March-April. By fourth grade, doctors still didn’t think there was a connection. Instead, they wanted to run neurology tests which all came out normal. She is in fifth grade now and I still hold firm to the belief that this is a reality for her. So glad I stumbled upon your article!

    • Missy says:

      They simply don’t know. Dr. Doris Rapp wrote many years ago on how allergies effected kids’ behavior and moods, but few still see it.
      My sons, now young adults, would be irritable and ill like clockwork, every October and March when they were growing up. It was clearly seasonal and related to fall and spring pollens.
      I have almost year round pollen allergies and am fighting anxiety pretty bad right now with south Texas spring pollen. Wish they had more to offer us.

  7. Roberta says:

    Thank you so much for this article. I’ve been observing how every year I get different “symptoms” at different times—–heartburn/indigestion in the spring, anxiety in the fall. I’ve lived in Virginia all my life, and in spite of the fact that all of my family has been allergic to a variety of pollens I thought I was in the clear. I made an appointment with an allergist today to see what might be triggering these issues. I’m not canceling my psychotherapy quite yet, but it’s interesting to consider how allergies might be affecting my mental health. Thanks again!

  8. Jessie says:

    I have long suspected my allergies and anxiety are tied together. When the pollen counts get high, I start having anxiety attacks. I described my body as a “delicate ecosystem” to my husband, because if one thing gets “off” I start having issues. I’ve been outside a ton in the last few days, which has led to a runny nose, lots of drainage and headaches, plus fatigue, not to mention the huge mosquito bite welts I have all over my body, including my face. I have three young children, which means I don’t get to stop and rest when I feel run down due to allergies. I’ve had major allergies and sinus issues my entire life, so I’ve just learned to live with it and push through. I’ve never actually been to an allergist, but I do take an OTC allergy medication and nasal spray daily. I also have allergy-induced asthma, so I keep my inhaler on hand at all times. I have dermatitis around my nose, which gets worse when triggers are high. I grew up in the South, in the middle of a cornfield, in an old house with old windows and cracks between the floorboards. I now live even further south, where pollen levels are off-the-charts. I’ve fainted before, in the fall, when levels got too high, which caused me to have an anxiety attack because I freaked out about what was wrong with me. I’ve felt for so long that my anxiety symptoms and allergies were connected. I’m so glad to see other people see this connection, too, and that there is hope that doesn’t just include medicines for anxiety!

  9. AC says:

    My 2 Major Panic attacks and anxiety occurred when cedar levels reached high records in the past 3 years. It wasn’t too bad the first 8 years living here, then we moved to Dallas for 1 year, then moved back to San Antonio. When we moved back all hell broke loose. I spent and continue to try to find answers on why I developed this mental health issue of crippling anxiety and panic attacks, at one point feeling like someone suffering from depression. The only thing I’ve been able to narrow it all down to is the allergens. This year after getting a blood test done for allergies, it’s all coming together, unfortunately, the damage is done and now I’m working hard on trying to fix the anxiety. Here are my allergy results, This should be our last year in Texas and we will also be moving back to California, Hopefully before Cedar Season. I guess If I have to Choose between High Taxes and cost of Living vs Allergies and being miserable I will pay the extra taxes.

    0.63 H – Class 1

    BIRCH (T3) IGE
    0.64 H – Class 1

    71.70 H

    0.63 H

    3.55 H

    OAK (T7) IGE
    1.39 H

    ELM (T8) IGE
    1.02 H

    0.63 H

    0.43 H

    1.82 H

    4.42 H

    14.50 H

    2.03 H

    7.92 H

    0.45 H

    NETTLE (W20) IGE
    0.78 H

    SHRIMP (F24) IGE
    5.15 H

  10. Jay J. says:

    Now that grass season has subsided in Seattle, I was interested to see if there is any new research on the link between allergies and anxiety/mood/fatigue. Allergies creep up on me until the grass pollen subsides, and then I realize what how much better I feel. Although it can take 5 years, allergy shots are very much worth it too. Once you begin to understand the affects on the neurology system from allergy attacks, it isn’t so much anxiety as it is like a being off kilter. I would add that histamine triggers horrible migraines, particularly if I were to have a beer. I haven’t paid much attention to my diet, so much thanks to the author of this article. I know now that I have to diligently manage things during the Spring, but I have been very interested in this topic, since five years of allergy shots markedly ratcheted down both my allergies, and anxiety.

    I meet so many allergy sufferers, but wonder it they have been able to see how the two can be linked. Even though seasonal allergies are a pain in the ass in Seattle, they were absolutely debilitating while growing up in Kentucky. Symptoms included fainting, asthma attacks, and frequent migraines. Really, it isn’t difficult to understand how all of that can be a bit of a downer. But the real culprit is histamine’s affect on the nervous system, which is something altogether different.

  11. Kathy says:

    So happy you reported how allergies cause anxiety for you, too. I have had anxiety attacks in the past in the spring. I live in Keller, Tx. I take allergy shots ever other day, but this spring is bad. We just got back from a week long trip to Oklahoma and I have had a headache nearly everyday. My anxiety is very high and I feel a little depressed. Definetely foggy headed. It’s always worse when I come back from a trip. Going to see my allergist next week.

  12. jj martin says:

    Very informative article. Will definetly see into this because I have gotten worse every year with allergies and anxiaty symptoms.
    Thank you sir!

  13. Texmom says:

    One of the better articles I have seen on this.
    I live in the Austin/San Antonio area of Texas and every year seems worse. Now, I think I only have a few weeks that I am not having bad allergies. Daily Zyrtec seems to do nothing.
    Felt anxious today along with a sudden sore throat and food reaction. Turns out oak pollen just started up…sigh.

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