Dr.Kamini Silvarajan MD/AAAM

Editorial Board: Dr.Kamini Silvarajan MD/AAAM

Immune System Asthma

Asthma And Your Immune System

YES! the same system that helps to protect you from infections, your immune system, can also be the cause for your worsening asthma.There will be noticeable happenings identically like runny nose, watery eyes and sinus congestion, your peak flows are lower, you are wheezing more, and you may experience more shortness of breath. So how it is here that the immune system and asthma are linked.
  1. Sensitization
  2. Early phase response
  3. Late Phase response
Inhalation of substances such as dander, pollen or dust mites where the substances bind to membranes(is a thin wall or film that allows only some substances to pass through it or that prevents the mixing of two substances) in your lung 

Ingestion of foods or medicines where the initial immune system reactions occur in the stomach 
Physical contact of skin with substances such as poison ivy(climbing plant of the cashew family that secretes an irritant oil from its leaves) 


he mast cell or IgE complexes produced in the sensitization phase, binding to the allergen thinking that it is a foreign invader.

Mast cells then release inflammatory cells called mediators (e.g. histamine*) that quickly travel throughout your body with the purpose of fighting off the foreign invaders such as bacteria and viruses.

You begin to experience symptoms of your body’s overreaction to the allergen. 

The immune system normally protects you against foreign bacteria and viruses. In asthma and other allergic diseases, the immune system may be the cause for your worsening symptoms.

Many asthmatics are atopic (denoting a form of allergy in which a hypersensitivity reaction such as asthma may occur in a part of the body not in contact with the allergen) where your immune system develops an exaggerated response to certain foreign substances or allergens. 

Your body’s immune system senses these allergens, perceives them as foreign, and begins to prepare to fight them off as a foreign body. 

The process that takes place is often referred to as the allergic cascade(stages in a process, each of which triggers or initiates the next), which generally occurs in three steps:-

Exposure To Allergen Under Sensitization(capable of producing an irritation or allergic reaction)

Initially when you are exposed to an allergen, sensitization, you will not usually have symptoms. You may be exposed to allergens that stimulate the allergic cascade through:-

Immunologically(the signs and symptoms of reactions of immune cells or antibodies to antigens), your body senses the allergen as foreign and sets off a cascade of events stimulating several different types of immune cells.

At this point, the allergen has triggered the allergy cascade, but you will not develop any symptoms or even realize that anything has happened. During subsequent exposures to the allergen, you may develop asthma symptoms as part of the early-phase response.

Early Phase Response – Re-exposure

With re-exposure to the allergen your immune system senses the allergen as foreign leading to:-

Histamine* – A compound that is released by cells in response to an allergic and inflammatory reactions, causing contraction of smooth muscle and dilation of capillaries.

The mediators react in different parts of your body causing your allergy symptoms. You may begin wheezing, coughing or feeling short of breath as the immunologic response causes swelling and narrowing of the airways in your lung. You may only experience runny nose or watery, itchy eyes. The immunologic response begins nearly immediately with symptoms occurring very shortly after re-exposure lasting three to four hours.

Late Phase Response

Beginning at the same time as the early phase response, but not causing symptoms for several hours, is the late phase response. Mediators(a go-between) released by the re-exposure to an allergen also stimulate other kinds of immune cells called eosinophils. Eosinophils contain substances that when released normally fight off infections, but in asthma, the cells damage the lung causing more inflammation and worsening symptoms.

In the late phase, symptoms will not develop for at least four hours, but may last as long as 24 hours. Increased inflammation and obstruction of airflow may be more severe than what is seen during the early phase.

Understanding The Allergic Cascade And How It Benefits You

Current therapies generally and widely target specific parts of the cascade.

The most easily perceived or understood approach would be to avoid the allergens altogether and prevent the allergic cascade from occurring. While this may work for some allergens like specific foods and pet dander, other allergens like dust and molds may be more difficult, and medications are often needed.

First generation antihistamine drugs like diphenhydramine (Benadryl) or second-generation antihistamines like loratadine (Claritin) or cetirizine (Zyrtec) prevent allergy symptoms by inhibiting the inflammatory response of the mediators released during the early phase of the allergic cascade. 

Antihistamines prevent mediators, such as histamine, from binding to receptors in the nose and eyes that cause the allergic symptoms of sneezing, runny nose, congestion and watery eyes.

Bronchodilators* like Albuterol target the early phase of asthma causing a widening of the airways and relief of airway obstruction making it easier to breathe. 

Drugs with anti-inflammatory properties, such as steroids and leukotriene antagonists, may be used acutely to decrease the late phase response or used as a preventive measure to attempt to keep the late phase response from occurring at all.


A bronchodilator* is an asthma medication that relaxes the smooth muscles and functionally enlarges the size of the airways of the lung. Bronchodilators come as both short-acting beta agonists (SABA) and long-acting beta agonists (LABA).

Bronchodilators improve symptoms by opening up the airways of the lung. This decreases asthma symptoms and makes it easier for you to breathe.

SABAs are used as a quick relief medication, while LABAs are used as a controller medication. Bronchodilators can be prescribed as both inhaled and oral forms, although the inhaled form is preferred.


Finally, allergy shots or immunotherapy may be used in an attempt to desensitize a patient to an allergen. With the shots your body decreases its foreign invader response and the immune system generates less IgE and hopefully does not react strongly to a particular allergen.

After reading the above, a better understanding of your immune system (is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells) will give you a better understanding of what might be causing your asthma symptoms to worsen and help you gain better control of your asthma.

DISCLAIMER :- The information contained above are for educational and basic guide purposes only, and should not be used as a substitute for any ASTHMA personal care unless otherwise have consulted your doctor or medical healthcare providers for diagnosis and treatment of any concerning symptoms or medical condition.