Intro: Duly Noted, a Health and Care podcast, is the official podcast series of Duly Health and Care. Each podcast features physicians or team members discussing groundbreaking topics and innovations that help listeners reimagine and better understand an extraordinary health and care experience.

Cheryl Martin (Host): As allergy season seems to be around these days, many people wonder why their allergy medication no longer works or doesn't work as well as it used to. Dr. Andrey Leonov is here to discuss why this could be happening to you, as well as the best ways to treat seasonal allergies. He's an Allergy, Asthma and Immunology specialist.

Host: This is Duly Noted, a health and care podcast. I'm Cheryl Martin. Dr. Leonov, delighted you're on today.

Andrey Leonov, MD: Thank you. It's a pleasure to be here as well.

Host: About 25% of the US population has seasonal allergies. So, please explain what seasonal allergies are and how they differ from other types of allergies.

Andrey Leonov, MD: Seasonal allergies are basically an immune response to things like pollen or mold spores that are present in our environment and are airborne on a seasonal basis. For example, when trees pollinate primarily in the spring time here in the Midwest or when grass pollinates a little bit later in the spring and summer, or when weeds and the ragweed and other plants may be pollinating later in the summer and into the fall, as well as mold spores that may be present also on a seasonal basis. Those are in our environment, and we end up inhaling them. And if our immune system is set to overreact to them, rather than quietly ignore them, then this overreaction causes the symptoms that we call symptoms of seasonal allergies. And the symptoms typically are, as allergy sufferers very well know, congestion, itching, sneezing, mucous production, all of that stuff.

Host: And a person who suffers from allergies year round.

Andrey Leonov, MD: For those people, they either may have just a lot of allergies that are seasonal, that are just present most of the seasons, or if it is a person who also has symptoms when nothing is growing like during the winter time, those people will have allergies to things that are primarily indoors, like dust mite or some indoor molds or possibly pet dander if they have pets.

Host: So, one of the top treatments for seasonal allergies is over-the-counter and prescription allergy medication. But many people who take these medications realize they may stop working over time. So, what can cause medications to lose their effectiveness?

Andrey Leonov, MD: It's an excellent question and I would consider it as a two-part question. Part number one is medication that patient have found useful before have stopped being useful because patient has gotten used to that medication. And there is a mechanism for how this might happen for certain medications. Specifically, it's a very well known phenomenon for antihistamines such as diphenhydramine or cetirizine or fexofenadine, the medications that we can easily find over-the-counter. And if you speak to many allergy sufferers, you will find that for a lot of those people they had to go through different iterations of these medications over time because exactly of that reason, they just stopped working whereas they worked in the beginning. And the mechanism there is our own body's response to seeing that medication on a constant basis over a long time. It is a complex mechanism that basically ends up being felt like medication is not working anymore. So, we may need to push the doses higher or we need to switch to a different antihistamine altogether.

Now, second part of this question is, what if medication continues to work, but the allergies have gotten just more intense? Meaning that our immune system just is becoming more overreactive to the allergen, or maybe there is more allergen. For example, over the last few years, what we have been noticing is that the allergy seasons become more intense for some people, not for everybody, but for some people we definitely see that. And we think it might be, partially because there is just more allergens present and those people are exposed to more allergens in a more intense level. And that's why medications, even though they are working to some degree and used to be able to handle the lower level of allergen exposure, now they're just not enough.

Host: I believe you have already touched on my next question, which is going to be how does a body develop resistance or tolerance to allergy medication? So, I'm asking now, are certain individuals more predisposed to this than others?

Andrey Leonov, MD: We think that there is definitely personal predisposition that probably has to do with individual metabolism, either of the medication or the receptors that the medication is being used on. The short answer is yes.

Host: So, are there any specific allergy medications that are more likely to lose their effectiveness?

Andrey Leonov, MD: We see that more with antihistamines. The ones in that category are, for example, cetirizine, fexofenadine, loratadine; levocitirizine, which is an iteration of or a cousin, if you will, of cetirizine; diphenhydramine. All of those medications are grouped under the umbrella antihistamines based on the mechanism of how they work. And antihistamines do tend to sometimes, for certain individuals, induce this phenomenon where a person gets used to it, if you will, or more precisely, the efficacy of the medications become less because of certain changes at the interaction of the medication and the cells through the receptors. So, certain changes there cause the medication to be less effective.

Host: So, if your tolerance builds for one type of allergy medication, does that mean you develop a higher tolerance to all allergy medications?

Andrey Leonov, MD: Not necessarily.

Host: So, that's good news then.

Andrey Leonov, MD: It is good news in a way. The problem here is we do not have a lot of categories of the medications for allergies, that, you know, we can pick and choose from. So, there are intranasal steroids, which are your usual nasal sprays that we use. There are also antihistamine nasal sprays. And then, there are antihistamine tablets. And then, there are a few others that are not used as often, but also could be effective, like anti-leukotrienes. However, two major categories of the medications, which are antihistamines and nasal steroids, those are the more widely and commonly used. And if a person develops a level of tolerance to antihistamines, then they may be only left with nasal steroids for efficacy.

Host: Okay. So, doctor, how can allergy sufferers determine if their medication is no longer working effectively? What are some signs they should look out for?

Andrey Leonov, MD: Now, primarily, it's how well are the allergies controlled, as they go through their usual allergy season. If they find that they have difficult time getting the symptoms under control with what used to control the symptoms well, then definitely part of the answer to the question why is this happening would be possible development of tolerance to the medications.

Host: So, what advice would you give to those who are struggling now with allergy symptoms and they're finding little relief from their current medication? What other treatment options are available?

Andrey Leonov, MD: There are several treatment options that we have to choose from. One is we need to answer the question of why do they experience more symptoms with the same medications that they continue to use. And to answer that question, usually what happens is they would visit with an allergist, testing would be done to determine what they are allergic to. And based on their current allergen profile, we can kind of gauge a little bit better what is happening with their symptoms. Then, if we think that it is the tolerance that is being developed, we can choose from another class of medication. For example, instead of antihistamines, we can try nasal steroids. And we can also guide the patients in terms of limiting their exposure to the allergen, best done in a specific manner once we know what they're allergic to, more precisely after the testing. That's one. And two, we can consider a process called immunotherapy where we try to induce a certain level of desensitization to those allergens by doing allergy injections.

Host: It's my understanding that in your work, you also provide patients with a personalized allergy treatment plan. Is that correct?

Andrey Leonov, MD: That is correct. And that's where the value of understanding what they are allergic to in a more precise manner by doing the test, by getting a very accurate history of what is happening with certain exposures. And by designing the immunotherapy plan that is based on the patient's specific exposures and specific things that they are allergic to, is very helpful to circumvent the issue of not responding well to the medications.

Host: Anything else in closing you want to add on the best ways to treat seasonal allergies or anything about your practice there?

Andrey Leonov, MD: What we do as allergists and what we pride ourselves upon is very precise and thorough investigation of what person's specific allergies might be and how to develop that personalized plan for allergy treatment. The best way to approach seasonal allergies or even non-seasonal allergies are to have a detailed look at the symptoms and the triggers and then have a complex multifactorial or multifaceted approach to management of this allergy from multiple angles.

One angle is controlling the exposure. Second angle is controlling the symptoms and that's where medications become very handy and understanding of what works and what doesn't work and why becomes also very handy there. And the third angle is devising the immunotherapy plan that would help to essentially decrease the level of allergy for those specific allergens by doing the desensitization approach or the allergy injection approach.

Host: Dr. Andrey Leonov, thank you so much for sharing your expertise on seasonal allergies and also just talking about the best treatment plans. Thank you so much.

Andrey Leonov, MD: My pleasure. It was great to talk to talk to you.

Host: For more information, visit dulyhealthandcare.com. That's dulyhealthandcare.com. If you found this podcast helpful, please share it on your social channels and check out the full podcast library for other topics of interest to you. This is Duly Noted, a podcast from Duly Health and Care. Thanks for listening.