Living with Eosinophilic Asthma

Living with eosinophilic asthma (also called eos asthma or e-asthma) means learning how to keep your airway inflammation under control so you can breathe easier and stay active. Management goes beyond taking medication. It’s about understanding your triggers, following your treatment plan, and working closely with your healthcare team.

Regular checkups, taking medications as prescribed, and watching for the early signs of an asthma attack can make a difference. Seek out support from family, friends and doctors who understand eos asthma. With the right care, many people with the condition are able to limit flare-ups and enjoy a healthy, active life.

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Start by learning more about eosinophilic asthma

When you know more about eosinophilic asthma, you feel more confident in managing it.

Eos asthma is a severe form of asthma. It starts with microscopic white blood cells called eosinophils (ee‑oh‑SIN‑oh‑fills). These cells normally fight germs, but when too many gather inside the airways (breathing tubes) of your lungs, you experience inflammation where the tubes swell and get tight. That swelling makes it difficult to breathe.

Talk with your doctor and get tested to find out your type of asthma. When you know more, you can…

  • Understand asthma. Eosinophils increase in your body and cause your lungs to feel tight. When you know why this is happening, the steps to fix it make sense.
  • Fewer surprises. You can spot early signs of airway inflammation and act fast.
  • Confidence. Instead of feeling unsure or anxious, you know, “I’ve got tools to handle this.”
  • Improve communication. The more you know, the easier it is to talk to others about it.

Focus on What You Can Control

When you understand what is happening in your lungs and your immune system, you can steer the ship, not just ride the waves. Learn how to improve your asthma management in your daily life.

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Tips for daily asthma management

Develop a routine to help you manage your eos asthma symptoms. Here are some suggestions:

Routine, routine, routine

  • Take your daily controller inhaler (usually an inhaled corticosteroid) at the same time each day, even when you feel fine. This maintenance medicine can help control and calm airway inflammation.
  • Stay on track with other prescribed medications, such as biologics which are add-on treatments with daily controller inhalers. Biologics are advanced treatments for moderate to severe eosinophilic asthma.
  • Check your lung function as your doctor has instructed you to do, using a peak flow meter.
  • Stay consistent. This helps reduce the risk of flare-ups and keeps your eos asthma under control.

Regularly review your Asthma Action Plan

  • Develop an Asthma Action Plan with your healthcare provider. This plan is a step‑by‑step guide to help you control symptoms daily and manage flare-ups when they happen.
  • Review your plan with your healthcare provider twice a year and update it as needed.

Keep your medication close and up to date

  • Carry your inhaled quick-relief medicine (usually albuterol) with you and use it when symptoms occur, as prescribed.
  • Write down when your medicine will run out or expire. Refill it early so you won’t run out. 
  • Always take your quick-relief inhaler (and any other asthma medicine) to work, school and trips. That way, you’re ready if symptoms emerge.
  • Do not rely on oral corticosteroids (also called oral steroids) to treat symptoms. These bring a risk of side effects from both short- and long-term use.

Be aware of your asthma symptoms

  • Watch for any new symptoms, such as a cough, wheeze, or chest tightness. Take note if you feel your asthma is poorly controlled.
  • Detail your symptoms in a diary or symptom tracker. Your notes will help your doctor see patterns and determine if you need to make changes to your medications.

Know how to use your inhalers and devices

  • Confirm with your healthcare provider that you are using proper technique with your inhaler and other asthma management devices. This will help you make sure you are getting the right amount of medicine.

How to use your metered-dose inhaler (general instructions)

  1. Shake the inhaler.
  2. Prime the inhaler by spraying a 1-2 puffs into the air.
  3. Stand or sit up straight and breathe out completely to empty your lungs as much as possible.
  4. Hold the inhaler upright with the mouthpiece at the bottom and the top pointing up.
  5. Put the mouthpiece in your mouth and close your lips around it. (Some inhalers recommend positioning the mouthpiece about an inch from your open mouth.)
  6. Inhale slowly, then press the canister a split-second later.
  7. Breathe in slowly for 3–5 seconds.
  8. Hold your breath for 10 seconds, then breathe out slowly.
  9. Repeat steps 3 through 9 if you need to take a second dose.

Instructions for a dry powder inhaler and slow-moving mist inhaler are similar but may have subtle differences. Always check your medication’s prescribing and patient information for specific instructions.

To ensure you are using your inhaler correctly, ask your doctor to watch you use the device. This can be done at a doctor’s appointment.

Follow your Asthma Action Plan and your doctor’s recommendations

  • Stay away from your known triggers.
  • Keep prescriptions filled so you never run out.
  • Go to every follow‑up visit even if you feel okay.

What is a peak flow meter?

A peak flow meter is a handheld device that measures Peak Expiratory Flow Rate (PEFR). This is the maximum speed you can force air out of your lung’s large airways. PEFR can show how well your lungs are working. Using a peak flow meter can help you identify the early warning signs of an asthma attack.

How to use a peak-flow meter (general instructions)

  • Blow hard into the peak flow meter each morning before taking your medication. 
  • Write the number in a journal so you have a record and can track symptoms.
  • Green = good, Yellow = caution, Red = contact your doctor.
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Lifestyle changes for living with eosinophilic asthma

Making certain lifestyle changes can help you keep eosinophilic asthma under control and improve your quality of life.

1. Identify and avoid eos asthma triggers

Common asthma triggers such as cigarette smoke, strong odors, respiratory viruses, cold air and air pollution can inflame your airways. Allergens such as pollen, mold, pet dander and dust mites can also trigger symptoms. Once you have figured out what affects you most, find ways to reduce your exposure to it.

How to minimize common asthma triggers: 

  • Smoke and strong smells. Avoid cigarettes and cigarette smoke when possible. If someone around you smokes, ask them to do so outside and away from doors or windows. Don’t use scented candles or strong cleaners.
  • Cold air. Cover your mouth with a scarf on chilly days and warm up indoors before outdoor play.
  • Respiratory infections. Try to avoid people who are sick with a cold or the flu. Wash hands to keep germs and bacteria at bay.
  • Pollen. Check the daily pollen count (use apps like AirNow). On high‑pollen days, stay indoors as much as possible, keep doors and windows closed, set your A/C to “recirculate,” and wear a hat and sunglasses outside to reduce your exposure to pollen.
  • Mold. Run the bathroom fan during showers, fix leaks quickly right away, and keep humidity levels between 30% and 50%.
  • Pet dander. Try to keep pets in certain rooms, and keep them out of your bedroom or any room where you spend a lot of time. Brush pets outdoors and wash your hands after play.
  • Dust mites. Wash bedding in hot water each week. Use dust‑mite covers on pillows and mattresses. Vacuum carpets using a HEPA filter.
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2. Healthy eating and appropriate exercise

Maintaining a healthy weight range and adopting a healthy lifestyle can help you control symptoms.  Extra weight can press on your lungs and make breathing more difficult. Exercise can keep the lungs and heart strong.

Healthy eating for asthma

  • Add color. Fill half your plate with bright fruits and veggies.
  • Pick smart proteins. Beans, chicken, fish, eggs or lean beef help muscles stay strong for breathing.
  • Choose whole grains. Try brown rice, oats or whole‑wheat bread for steady energy.
  • Drink water first. Swap one sugary drink a day for water.
  • Small swaps. Even switching something like fruit or protein for chips once a day can make a difference over time.

Asthma-friendly exercise

  • Try activities like walking, biking at an easy pace, swimming or yoga. These are consider quality exercises for people with asthma because they help control breathing and don’t trigger symptoms. If you have not exercised in a while, talk with your healthcare provider about developing an exercise plan.
  • Take your quick-relief inhaler 15-20 minutes before exercise, if prescribed by your doctor. This can pre-treat asthma and keep symptoms under control.
  • Warm up for 5-10 minutes before exercise, keep your quick-relief inhaler nearby, and cool down after your workout.
  • If cold air or pollen bothers you outside, exercise indoors on those days.

Treating eosinophilic asthma’s comorbidities

If you have eosinophilic asthma, you may experience other conditions linked to Type 2 inflammation. Managing these comorbidities effectively can improve your asthma control and overall quality of life.

Common asthma comorbidities and tips on how to manage them:

  • Stuffy or runny nose (allergic rhinitis). Saline nasal sprays or rinses can help clear mucus and allergens that may worsen airway inflammation.
  • Nasal polyps (small growths in the nose). These small, non-cancerous growths in the nasal passages are often driven by Type 2 inflammation. Treatment options include nasal corticosteroid sprays, biologic therapies or minimally invasive surgery. An allergist or ENT (ear, nose, and throat) specialist can help determine the best approach to treatment.
  • Skin, eye, or pollen allergies. Conditions like eczema (atopic dermatitis), allergic conjunctivitis, and hay fever (allergic rhinitis) share the same inflammatory pathways as eosinophilic asthma. Managing these conditions can help reduce your overall inflammation burden and asthma symptoms.
  • Extra body weight. Carrying excess weight can worsen asthma symptoms and reduce lung function. Even modest weight loss can improve breathing, decrease inflammation, and enhance the effectiveness of asthma medications.

If you have any of these conditions along with eos asthma, speak with your doctor.

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Managing eosinophilic asthma: build a support system

Eosinophilic asthma can sometimes feel isolating. But you don’t have to manage it by yourself. Help can come from family, friends, other patients and healthcare providers.

Family and friend support

Living with a chronic condition can be hard, but the people close to you can help lighten the load. Here are easy ways they can help:

  • Share your triggers. If family and friends know smoke or pet fur bothers you, they can watch out for it, too.
  • Medication reminders. Ask for a reminder to take your asthma medicine, including when not at home.
  • Share your Asthma Action Plan. When family and friends know what asthma symptoms to look out for, they’ll know what to do in an emergency.
  • Bring a buddy to appointments. A parent, family member or friend can help you ask questions and understand instructions. 

Online Support Community

Joining an eos asthma patient community can be really helpful for finding support and advice from others. As much as friends and family can help, connecting with other asthma patients can help you feel less alone. You can learn how they handle everyday activities, including school, sports and vacations, as well as taking new medications.

Find a Local Support Group

APFED keeps a list of self-identified community-led support groups. Some groups host in-person meetings in their communities, while others connect patients and families through social media.

Professional support

It is important to acknowledge the feelings that are associated with a chronic disease like eosinophilic asthma. Feeling sad, anxious, or even angry about a disease is okay. Rather than letting these feelings overwhelm you, expressing them can help give you a sense of control. Seek professional counseling if you need help coping with chronic illness.

Support for Caregivers: Practical Tips

Caring for someone with eosinophilic asthma requires help with medicine, watching for symptoms, and going to doctor visits. But it’s also important to take care of yourself. You matter, too! Here are some ways to stay strong and feel more in control:

Take care of you

  • Take breaks. Rest is important. Even a short walk or quiet time with a book can help you recharge.
  • Talk to others. Share your feelings with a friend or support group for caregivers of people with chronic illness. You’re not alone.
  • Ask for help. It’s okay to lean on family, friends, or your community.
  • Eat, sleep, and move. Try to eat healthy meals, sleep well, and move your body every day.
  • Do something fun. Make time for things you enjoy. Fun helps reduce stress and brings joy back into your day.

Be ready for eos asthma

  • Keep a medicine log. Write down when medicine was taken and when refills are needed. A calendar or phone reminder works great.
  • Watch for changes. Look for small signs that asthma may be getting worse. Such as, is breathing more difficult when resting? These changes may be a sign to contact your doctor
  • Know your Asthma Action Plan. Read it over and ask questions so you know what to do in green, yellow, or red zone situations. This plan helps everyone stay safe.
  • Feel ready for doctor visits. Bring a list of any new symptoms, all the medicines being taken (even non-asthma ones), and list of questions you want to ask. It helps the visit go smoothly and ensures nothing gets missed.
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Managing your professional or academic life alongside eosinophilic asthma requires understanding your rights and communicating your needs.

If you have eosinophilic asthma, you may be able to request reasonable accommodations at work and school. In the United States, a few laws can be particularly helpful: 

Americans With Disabilities Act of 1990 (ADA) 

  • ADA is a U.S. civil rights law that says people with disabilities must get the same opportunities as everyone else at work, in school, shopping, traveling, and more. 
  • A disability is any medically-documented physical or mental condition that seriously limits daily activities (like walking, seeing, breathing, or learning). Severe asthma is considered a disability. 
  • According to the ADA, you may ask for reasonable accommodations (changes) that help you do your job but do not create additional costs or difficulty for the employer. The ADA applies to employers that have 15 or more employees.

​​Common asthma accommodations under the ADA (from the Equal Employment Opportunity Commission) include:

  • Cleaner air. No‑smoking or fragrance‑free rules near your workspace, air purifiers, or moving your desk away from a common area.
  • Schedule flexibility. Extra breaks to use an inhaler or take medicine, or working from home on high‑pollen days.
  • Protective gear. Providing masks or respirators if dust or fumes are part of the job.
  • Leave for treatment. Short time off for doctor visits or a flare‑up.

If you need special accommodations to do your job effectively, speak to your employer to find reasonable solutions. 

Family and Medical Leave Act (FMLA) 

  • The FMLA allows eligible employees to take up to 12 weeks of unpaid leave each year for certain family or medical reasons, without losing their job or health insurance. When you return, your employer must give you the same or an equivalent job. 
  • To qualify, your employer must have at least 50 employees within 75 miles, and you must have worked there for at least 12 months and 1,250 hours during that time.

Section 504 of the Rehabilitation Act of 1973

  • Section 504 is a U.S. civil rights law that requires schools receiving federal funding to provide equal access to education by offering appropriate support and accommodations to students with disabilities.
  • Asthma is considered a disability under Section 504 because it makes breathing hard, which is a “major life activity.”

How to get a 504 Plan:

  1. Submit a written request. A parent or guardian should submit a written request to the school, asking for an evaluation for a 504 Plan. This is sometimes called a “504 referral.” The letter should explain how the student’s asthma impacts their ability to access learning or participate in school activities.
  2. Provide medical documentation. The school may ask for supporting documentation, such as a note from your child’s healthcare provider describing the diagnosis, how asthma affects your child at school, and recommended accommodations (e.g., access to medication, avoiding certain triggers, modified physical activity).
  3. Participate in a 504 team meeting. The school may coordinate a meeting with parents, teachers, school nurse and other staff to discuss the needs and accommodations. They can also meet to develop a plan. 
  4. Develop and implement the 504 Plan. The plan should outline the specific accommodations and supports the school will provide. Once finalized, all school staff who work with the student are required to follow it.
  5. Know your rights. If the plan is not followed or if the school denies a request without proper evaluation, parents have the right to file a grievance with the school district or a formal complaint with the U.S. Department of Education’s Office for Civil Rights (OCR).

For more information about setting up a 504 plan, visit APFED’s website

Common 504 accommodations for asthma include:

  • Keeping an inhaler or nebulizer with the student (or in the nurse’s office).
  • Extra time to get to class or recover after coughing.
  • Skip or modify PE when the air is cold, smoky, or full of pollen.
  • Permission to drink water during class to ease coughing.
  • Make‑up work for days missed during a flare‑up without a grade penalty.
  • Fragrance‑free classroom or seating away from strong smells.
  • Allow late arrival if morning breathing treatments take extra time.

Additional laws that may apply to asthma: 

Need help affording your asthma medications?

  • Many drug makers offer coupon cards or free patient‑assistance programs. Allergy & Asthma Network lists them on its Patient Medication Assistance page.
  • Understanding your health insurance plan helps keep surprise bills away and allows you to choose inhalers that you can afford. Call the member services number on your card or ask a pharmacist to guide you through the drug formulary. This way you will know the co-pay for each of your medications. 
  • If you have no insurance, check your state’s Children’s Health Insurance Program (CHIP) and Medicaid programs. Some community clinics may also offer medicine on a sliding‑scale or free‑drug basis.
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Finding an eosinophilic asthma specialist

Most people diagnosed with eosinophilic asthma see a specialist. You may be referred to a board-certified allergist and immunologist (allergy doctor) or a pulmonologist (lung doctor).

Why a specialist matters

  1. Correct diagnosis. Allergists and pulmonologists use more specialized tests, such as mucus tests and blood tests, to measure the eosinophil count. They can help identify the type of asthma that you have so that it can be treated appropriately.
  2. Tailored treatment. These doctors may have more experience with more advanced “targeted” medicines called biologics. These medications are used when daily controller inhalers are not enough for maintenance medicine.

You might also visit an ENT doctor (ear, nose, and throat) for chronic rhinosinusitis and/or nasal polyps (sinus or nose problems). If you need emotional support, ask for a referral to a mental health specialist or counselor.

Managing a chronic illness requires a strong doctor‑patient relationship. It is important to find a specialist who is both knowledgeable about eos asthma and to whom you are comfortable with.

A yellow icon showing a magnifying glass over the letter "A" in the center, symbolizing search or analysis related to text or language.
  • American College of Allergy, Asthma & Immunology (ACAAI) Find an Allergist tool. A search feature to help you find an allergist in your area.
  • American Academy of Allergy, Asthma & Immunology (AAAAI) Find an Allergist tool. Locate an allergist/immunologist close to where you live.

Preparing for your appointment

Doctor visits are often short, so planning ahead helps you remember the important questions and leave with clear answers. Here is a list of things to write down to bring with you:

  • List your symptoms. Write down any symptoms like dry cough, wheeze, or tight chest, along with the times they occur. Consider using an asthma tracker.
  • Write your concerns. Note how asthma affects school, work, sports, sleep or mood. List how often you use your quick-relief inhaler.
  • State one clear goal for the visit. Some examples: “Are there any other treatment options? I feel like the current one isn’t working.” Or “My breathing has been great, can we see if I can lower my dose?”

Ask your doctor(s) questions about severe asthma

Write your questions on paper and bring it with you to your doctor appointment. This can keep the appointment on track. Some questions to ask may include:

  • What breathing tests or procedures will be performed? How often?
  • What treatments do you recommend, and why?
  • How will you know if the treatment is working?
  • Will I need to continue taking any medications? Any special instructions?
  • How will my information be shared among specialists? Is a care coordinator available?
  • Will I need special accommodations at work or school?
  • Are there clinical trials I might be eligible for?
  • What will this cost?

Update this list of questions prior to every appointment. This way you and your doctor can create the best treatment plan together.

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Get an eosinophilic asthma treatment plan

Managing eos asthma starts with creating a personalized treatment plan with your doctor.

1. Get an Asthma Action Plan. This document is developed by you and your doctor. It shows:

  • How to treat your asthma daily.
  • What to do when symptoms get worse.
  • How to handle situations such as exercise, when you have a cold, or a virus.

You can download an Asthma Action Plan template and bring it with you to your next doctor appointment.

2. Have a written plan for medications. List the medication name, dose, when to take it, expiry dates, and any special notes so you never guess. Need help paying? See Allergy & Asthma Network Patient Assistance page.

3. Keep follow‑up visits. Your doctor may want to test your lung function to be sure your treatment plan is working. Do not skip an appointment even if your asthma is feeling well.

Questions and answers (Q&A) about living with eosinophilic asthma

Managing eosinophilic asthma is oftentimes more than just taking medications. It’s making lifestyle adjustments at home, work and/or school. It’s ensuing that your symptoms are under control so you can life your best life possible. Here are some common questions we’re asked about eos asthma, along with answers. If there’s a question you feel should be added, please email our editor.

Yes. Moving your body is good for your lungs and heart – as long as your asthma symptoms are well controlled. If your symptoms are not well controlled, check in with your doctor before exercising.

When exercising, always keep your quick relief inhaler close by. Your doctor may advise you to use it to pre-treat your asthma before exercise. Be sure to warm up first. You may want to pick more gentler exercises, like walking, biking, swimming or yoga.

If you start to cough or feel tight, stop, use your inhaler, and rest. With these simple steps, you can stay active and safe.

Yes, severe asthma can make you feel more tired. When you have airway swelling, every breath takes extra effort. This can tire your muscles. Night‑time coughing or shortness of breath can also wake you up. Disrupted sleep leaves you worn out the next day. Maintaining your asthma care routine will help reduce the risk of having uncontrolled asthma and help you feel more rested.

Severe asthma can be considered a disability. Several U.S. laws say a disability is any health problem that makes a major life activity, like breathing, hard to do. Severe asthma fits that rule. 

Eosinophilic asthma is a type of severe asthma. If you are diagnosed with eosinophilic asthma and your symptoms are severe despite taking medications as prescribed, it may mean you have uncontrolled asthma.

You may need more advanced treatments such as biologics. Biologics target eosinophil count production at the cell level, work to reduce inflammation and keep airways open.

Asthma and allergic conditions can run in families. Having a parent or sibling with asthma may put you at higher risk for eos asthma, but it does not mean you will definitely develop the condition.

There is no vitamin, supplement, herb or “natural” pill for treating eos asthma. Further, these should never take the place of doctor‑prescribed medications.

Healthy habits like eating a healthy diet, getting appropriate exercise, and practicing calm breathing techniques can help your lungs. These lifestyle approaches work with your asthma medicine, not in place of it.

Always check with your doctor before trying any new supplement or non-medical remedy.

Eosinophilic asthma is not typically set off by food or food allergens. So there is no special food that people with eosinophilic asthma should avoid.

However, everyone’s triggers are different. If you have both eosinophilic asthma and food allergies, your doctor may tell you to avoid your food allergens. A food-allergic reaction can lead to or mimic an asthma attack. Some people with eosinophilic asthma also have other eosinophil-associated diseases. This may include eosinophilic esophagitis (EoE), in which food can be a trigger.

Talk to a doctor if you suspect certain foods are making your asthma symptoms worse.

And remember, eating a healthy, balanced diet can help you feel better overall.

Stay informed about eos asthma

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Glossary for Eosinophilic Asthma

Allergen: A normally harmless substance, such as pollen or foods, that triggers the immune system to overreact in response. In some types of reactions, the body responds immediately and releases a chemical called Immunoglobulin E (IgE). In other reactions, called “cell-mediated,” the reaction can be delayed as immune cells in the body errantly attack the substance.

Allergy: An abnormal immune system response to any stimulus, including food, pollen, medications or insect stings. The classic working definition used by most physicians only includes immediate response allergic reactions (IgE-mediated).

Anesthesia: A medically-controlled, temporary loss of sensation or awareness.

Antibody: A protein produced by the immune system that fights against foreign substances or toxins, called antigens.

Asthma: A long-term lung disease. It causes episodes of coughing, wheezing, chest tightness, and shortness of breath. Mucus can cause spasms in the bronchial tubes, making it difficult to breathe. Symptoms can be mild or severe, and sometimes life-threatening. Asthma may result from an allergy or other hypersensitivities.

Autoimmune disease: A disease in which a part of the body’s immune system attacks its own cells that make up part of the body, such as skin, connective or joint tissue, intestinal tissue, nerve cells, etc.

Biologic therapies: These medications target specific cells and pathways that lead to inflammation. They are typically administered as an injection or infusion every 2-4 weeks. They are designed to treat the source of symptoms, rather than the symptoms themselves.

Biopsy: A tissue sample.

Bronchodilators: An inhaled medication that relaxes and opens the airways to relieve asthma symptoms such as coughing, wheezing, chest tightness and shortness of breath.

Bronchoscopy: A procedure performed under anesthesia by inserting an instrument called a bronchoscope (thin tube) through the nose or mouth. During the procedure, several small samples of tissue or fluid are collected (biopsy) and are then analyzed to determine the infiltration of eosinophils.

Clinical trial: Research studies performed in people to evaluate effectiveness and safety of medical, surgical, or behavioral interventions. Clinical trials may involve evaluating new medicine before it’s been approved to specifically treat a certain condition. The trials may involve a placebo group (inactive “medicine”) to see if the new medication offers an advantage over current treatments. Some trials are “open label,” in which all participants receive active medications or experimental treatments.

Complete Blood Count (CBC): A blood test that includes a count of all the red and white blood cells, platelets as well as hemoglobin, and hematocrit. Statistics about the red blood cells are also calculated and included in the test results.

Corticosteroid (aka “steroid”): A type of medication that is a synthetic version of cortisol or other hormones. When based on cortisol, this type of medication suppresses the immune system and may be used to treat allergies, asthma, eosinophil-associated diseases, autoimmune diseases, some forms of cancer, organ transplant rejection, and other diseases. It also may be prescribed to provide adrenal gland support in cases of adrenal insufficiency.

Eosinophil: A type of white blood cell that is part of our immune system. They help us fight off certain types of infections. They are produced in the bone marrow and migrate throughout the body. Elevated levels of eosinophils may be found in the blood and/or tissue, often as the result of an allergic response. Many conditions may cause abnormally high levels of eosinophils, including certain parasitic infections.

Eosinophil-associated disease: When a person has elevated numbers of eosinophils in their digestive system, tissues, organs, and/or bloodstream, without a known cause. These diseases are chronic and require long-term management.

Inflammation: Swelling of a tissue. It is part of the body’s response to tissue injury, irritation, or damage. Inflammation can occur anywhere in the body and from many different causes.

Parasite: An organism that has invaded the body that normally does not live in the human body or human digestive system.

Phenotype: Observable traits of a disease. Diseases may be grouped into phenotypes or subsets when they have common characteristics. Eosinophilic asthma is a subset of asthma or eosinophilic phenotype of asthma due to the elevated number of eosinophils in blood, lung tissue, and mucus.

Sputum: Mucus coughed up from the respiratory tract.

White Blood Cell (WBC): A type of blood cell that is involved in the immune system response to invading organisms (bacteria, virus or parasite). The different types of white blood cells include basophils, neutrophils, lymphocytes, eosinophils, and monocytes.

White Blood Cell Count with Differential (WBC with Diff): A type of blood test in which the total number of white blood cells in a measured amount of blood are counted. Each of the different types of white blood cells are counted and listed separately in the test results. This is more routinely referred to as a CBC with Diff, and includes RBC/HGB/HCT/Platelets.


Reviewed by:
William E. Berger, MD, FACAAI, is a board-certified allergist and immunologist who serves as a media spokesperson and Chair of the Medical Advisory Council for Allergy & Asthma Network. He is a Distinguished Fellow and Past President (2002-03) of the American College of Allergy, Asthma & Immunology (ACAAI).

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