All about allergies, p.1
All About Allergies, page 1
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Copyright © 2026 by Zachary Rubin
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Hardcover ISBN 9798217047970
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This book aims to provide useful information about allergy treatments to help guide your health conversations with your doctor, but it is not intended to replace your doctor’s diagnostic expertise and specific medical advice. Please consult with your doctor before making any health decisions, particularly if you believe you have any medical conditions that may require treatment. Publisher and author specifically disclaim responsibility for any liability that may result from the use of information contained in this book. Some names and identifying details of certain people mentioned in this book have been changed.
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Contents
Dedication
Introduction: You Are Not Alone
Part One
The Background
Chapter 1
The History of Allergies
Chapter 2
The Immune System
Chapter 3
The Anatomy of Allergies
Chapter 4
What to Expect at the Allergist’s Office
Part Two
Allergic Diseases
Chapter 5
Allergic Rhinitis and Non-Allergic Rhinitis
Chapter 6
Sinusitis
Chapter 7
Food Allergies
Chapter 8
Eczema
Chapter 9
Contact Dermatitis
Chapter 10
Urticaria and Angioedema
Chapter 11
Asthma
Chapter 12
Anaphylaxis
Chapter 13
Medication and Vaccine Allergies
Chapter 14
Mast Cell Disorders
Part Three
Treatment Options
Chapter 15
Over-the-Counter and Prescription Medications
Chapter 16
Immunotherapy
Chapter 17
Biologics
Chapter 18
Future Directions
Acknowledgments
Bibliography
Index
About the Author
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For everyone who has navigated their health with courage, even when they were misunderstood or unheard—this book is dedicated to you.
Introduction
You Are Not Alone
Growing up, I had a cow’s milk allergy, eczema, and seasonal allergies. My cow’s milk allergy disappeared early on, but I dealt with eczema throughout my childhood. I could never wear jeans as a kid because the fabric irritated my skin so much, so I had to wear khaki pants every day. That, combined with thick glasses and a bowl cut, gave me the stereotypical “nerd” look.
Don’t get me wrong, being a nerd rules, but in pop culture, a nerd has been synonymous with being weak, a loser, and clutching an inhaler. Think of Milhouse from The Simpsons, Mikey from The Goonies, and Stevie from Malcolm in the Middle. In Hitch, Albert either clutches his inhaler or uses it whenever he sees his crush, Allegra. However, when he throws his inhaler away, he finally has the courage to kiss her. It appears that his asthma is “in his head” and he can get what he wants only when he overcomes his anxiety. Like most allergic diseases, asthma is complicated and highly misunderstood, yet these diseases affect millions of people. People who do not live with these diseases may not realize how severe or life-threatening they can be for someone.
Today, despite being a nerd who spent high school more focused on learning to play the trumpet and hula hooping than impressing my classmates, I am a double board-certified pediatrician specializing in allergy treatment and immunology, who reaches millions on social media, where I raise awareness about allergic diseases and how they can be treated. My food allergies and eczema have resolved, but I still have some lingering symptoms of seasonal allergies that are under much better control, especially around dogs and cats. I never thought that I could have three dogs, but I have used what I have learned over the years to manage my allergies well.
I fell in love with medicine early on because I grew up being immersed in the field. I was fortunate because my dad is a pediatrician, so I spent a lot of time in his clinic and observing the impact that he had on his patients and their families. He was solving complex problems, helping families, and getting to know them along the way.
I wanted to be like my dad.
He told me many stories about when he was a medical student. His first lesson in medical school was about chest X-rays. His professor talked about a patient who died because he choked on a fishbone that, because it was made of cartilage, was difficult to identify on a chest X-ray. He talked a lot about the pace and expectations of medical school, and we realized that because technology had changed so much, medical education had likely changed a lot from when he was a student.
There were no premedical courses or clubs at my high school, so we decided to put in a lot of research to develop our own course, called Dr. Rubin’s Mini Medical School. My dad tested the curriculum on me to see if I could understand it as a high school student, and I became his first teaching assistant. The program was an eighteen-hour course separated into six sessions that had lectures and hands-on activities. I learned various physical examination and basic procedural skills that I helped teach to my classmates. I not only felt that medicine was my calling, but I also needed to find some capacity to teach.
Fast-forward to my third year in medical school; I tried keeping an open mind about what specialty I would pursue in residency. I thought about gastroenterology, dermatology, and radiology. Ultimately, I picked general pediatrics. While my experiences with my dad influenced me, pediatrics appeared to be a good fit with my personality and how I wanted to help people, especially children.
In my fourth year of medical school, plans quickly changed. I did an elective rotation in allergy/immunology, and I immediately fell in love with the specialty. Outside of a series of lectures on basic immunology, medical school did not dive into the breadth and depth of allergy. The diseases were complex, and the treatment options were expanding rapidly. I really liked the idea of practicing more preventive medicine and helping keep people out of the hospital as much as possible. It was also a bonus that I would be able to take care of people of all ages, so I could still see my pediatric patients when they were grown up.
After three years of general pediatrics residency, I completed two years of a fellowship in allergy/immunology. However, the beginning of the COVID-19 pandemic occurred right as I was transitioning from my fellowship training to my first job at a private practice. I had moved to a new state and there were limited connections for me. Social events were canceled, and primary care clinics were in survival mode. I decided to start posting on social media to connect with people locally.
At first, I was posting on Twitter (now X) and then I switched to TikTok, Instagram, and YouTube. This helped me connect with people locally. However, I quickly realized that there was a lot of incorrect health information (also known as misinformation) on social media, and I was seeing the effects of this misinformation in my clinic. One time, I met a parent who was putting povidone iodine in their child’s nose when their child was sick because they had seen it recommended on social media. Currently, we do not know the risks of putting iodine in a child’s nose, and there is no substantial evidence that it can help children.
I decided that I would focus on creating educational content that would either address health misinformation or teach people about a medical topic, such as how to use a nasal spray or epinephrine auto-injector, why most people should consider moving away from Benadryl, and why you could be allergic to exercise.
I also helped clarify people’s stories posted on social media about their health to provide more clinical information. There seemed to be an endless number of stories to talk about:
Facial swelling while exercising
A meat allergy due to a tick bite
Hives all over after being outside in the cold
An asthma attack
Sneezing attacks that would make people giggle
Allergy to water
Children suffering from a severe allergic reaction after eating food
Accidentally injecting an EpiPen into their thumb
Parents introducing foods to their babies outside an emergency room
Showing off allergy skin test results
The list kept going and going.
Have any of these scenarios happened to you? After spending a lot of time creating educational content, I realized that many people have felt that their experiences are unique and they are alone. There are only about 7,000 board-certified allergists in the United States, which means there is only roughly one allergist per 48,000 people. People who live in more rural or remote areas may not have any access to an allergist. I have received countless messages from people asking for help to understand their allergies, but it is unfortunately impossible to help that way.
I have been interviewed for TV and print media numerous times, and I have realized that people are constantly searching for health information from sources other than their doctors. There are not many allergists who get called on by the media for their expertise, but I have become one of the go-to resources to comment on breaking news or to teach the public about a specific topic related to allergic diseases.
Social media can be a great place to connect with other people and gather information. I created a lot of educational content over the years to teach people about various allergic diseases, but it is hard to keep the information organized online. I wanted to find a way to organize the education I have provided on social media.
That is why I decided to write this book.
It is not meant to be a textbook. This book is designed as a tool to help individuals understand the basics underlying allergies, to arm them with the information they need to live happier, healthier lives. The first part of the book sets the stage for understanding allergic diseases by covering the immune system and basic anatomy of allergies. The second part of the book covers in-depth information on most of the allergic diseases, with some myth-busting along the way. The third part of the book goes into more detail about various treatments and what the future may look like. You may choose to read parts of the book that apply to you, or you may choose to read the entire book to gain a better understanding of allergies and your immune system.
A quick medical disclaimer: This book is not meant to be specific medical advice and cannot diagnose your condition. The information in the book is meant to help you better understand your health and how to navigate the healthcare system. Any concerns about your health should be discussed with your doctor. Also, most of the treatments that I discuss are approved by the Food and Drug Administration (FDA) to ensure that treatments with the highest safety standards and effectiveness are the primary focus. The stories that I share in the book will have the names of the patients changed and minor details altered to help preserve anonymity except in cases involving public figures or stories told in the news.
I cannot tell you how many times I have been told that people have felt “written off” by their doctors because they could not explain what has happened to them. This does not necessarily mean your doctors don’t care about you. In medical school, there is very little training on how to diagnose and manage allergic diseases. Sometimes, it can be difficult to find the underlying cause of an ailment. Our understanding of how our immune system abnormally responds to foreign substances is constantly evolving. This book can also help healthcare professionals have a better understanding of allergic diseases.
Millions of people suffer from various allergic diseases. You are not alone. I hope the information contained in this book will help empower you to learn more about yourself and embark on a journey toward better health.
Part One
The Background
Chapter 1
The History of Allergies
Quod ali cibus est, aliis fuat acre venenum. [What is normal food to one, can be deadly poison for others.]
— Titus Lucretius Carus (circa 98–55 BC), De Rerum Natura
When I helped my dad start Dr. Rubin’s Mini Medical School, geared toward high school students, he and I created a curriculum that started with the history of medicine. My dad felt that even though many medical schools do not routinely teach the history of medicine, it is crucial to understand where medicine came from so that we have a better understanding of where we go from here. When I was growing up, when my family went on trips outside Illinois, he would take us to medical history museums if they were nearby. I became fascinated with how medicine has evolved so quickly. For example, the first recorded vaccine was given on May 14, 1796, by Edward Jenner to James Phipps, an eight-year-old boy, to protect against smallpox. That was less than 250 years ago!
Allergic diseases are nothing new—they have been around for thousands of years. However, over the past several decades, there has been a dramatic increase in the number of people suffering from these diseases. It is not clear why this is happening. While many people believe these diseases did not exist in the past, there is ample evidence that people have suffered from several conditions, such as food allergies and asthma, since antiquity.
Throughout history, allergies have puzzled and afflicted humanity, shaping our daily lives in ways that are often overlooked. This chapter will focus on the evolution of our understanding of allergies throughout time across the globe. Important historical figures in the field of allergy and immunology will be covered as well. I hope this chapter will spark a curiosity in you that will excite you to learn more about allergic diseases.
Allergies During Ancient Times
The earliest writings in human history are found in ancient Mesopotamia, the area between the rivers Euphrates and Tigris, which is in modern-day Iraq. The Mesopotamians developed a writing system called cuneiform around 3200 BC. They had writings about breathing: When the patient suffers from cough, he should drink a mixture of Lolium and rose powder dissolved in oil and honey. Afterwards he should eat a broth of pork meat. When he has to defecate, a fire should be lighted where he should direct his anus. Then he will be cured.
Some of the earliest physicians documented in human history came from ancient Egypt. The first is usually considered to be Imhotep during the 3rd dynasty at around 2600 BC. Two hundred years later, Ni-Ankh-Sekhmet was a physician to King Sahura during the 5th dynasty and is considered to be the first documented allergist. There is a stone at the tomb of the Pharaoh with the inscription “he cured the noses of the kings.” One of the oldest Egyptian medical texts, the Papyrus Ebers, was written around 1550 BC and contains twenty-one prescriptions for cough or difficulty breathing (i.e., dyspnea). Some of the ingredients listed include honey, dates, incense, juniper, and beer. A lot of the treatments described may have been used to treat asthma. Honey has been proven to help relieve a cough, but most of these remedies were ineffective for asthma treatment.
Ancient Chinese medicine used various plants to treat airway diseases, including wolfsbane and jimsonweed. A text titled Su Wen (meaning “Open Questions”) discussed through dialogue between the Yellow Emperor Huangdi and his minister Qi Po a disease that may have been asthma. One passage described how it was helpful to “avoid eating and drinking cold things and one should not wear chilly clothing.” We know today that one of the most common triggers for asthma symptoms is cold temperatures. One of the earliest descriptions of food allergy came from China. In the text Shi Jin-Jing (meaning “Interdictions Concerning Food”), the Chinese emperors Shen Nong and Huangdi advised pregnant women to avoid foods such as shrimp and meat. Individuals with certain skin lesions that may have been eczema were also advised to avoid certain foods. One of the earliest descriptions of urticaria, also known as hives, is more than two thousand years old and comes from China, where it was referred to as Feng Yin Zheng (wind-type concealed rash), which is similar to one of today’s traditional Chinese medical terms, Feng Sao Yin Zhen (wind itch concealed rash). Wind in traditional Chinese medicine is considered to be a major factor for developing urticaria, so other names for urticaria are Feng Zhen Kuai (wind rash lumps) and Feng Zhen (wind rash).
