• Also called as hypersensitivity.
• People who have allergies
have an immune system that
reacts to a usually harmless
substance in the environment.
• This immune response is
accompanied by a number of
stressful symptoms, ranging
from mild to severe to life-
• Substances that cause allergy are
known as Allergens.
• Examples of allergens include
pollens, dust mite, molds, dander,
pollutants, chemicals and foods.
• Allergic rhinitis is an
inflammation of the
mucous membrane of the
• Allergic rhinitis involves
reactions in the nasal
mucosa from repeated
allergen exposure that
• These reactions may be
seasonal or perennial.
Causes of Allergic Rhinitis
• Common allergens that cause
Seasonal Allergic Rhinitis are
grass pollens, tree pollens,
wood pollens and mold
• Allergens that cause Perennial
Allergic Rhinitis are pet
dander, dust and household
Symptoms of Allergic Rhinitis
• Stuffy, runny nose
• Post-nasal drip
• Red, itchy, and watery eyes
• Swollen eyelids
• Itchy mouth, throat, ears, and
• Sore throat
• Dry cough
• Headaches, facial pain or pressure
• Partial loss of hearing, smell, and
• Dark circles under the eyes
Complications of Allergic Rhinitis
Chronic nasal congestion in
Allergic Rhinitis may produce
• Otitis media/ Possible hearing
• Nasal Polyposis
• Sleep disturbance with or
without daytime fatigue
Complications of Allergic Rhinitis cont..
• Discomfort or uneasiness
• Difficulty in concentrating
• Decreased appetite
Immune System of the Body
• The immune system is the body's organized defense
mechanism against foreign invaders, particularly infections.
• Its job is to recognize and react to these foreign substances,
which are called antigens (e.g. viruses, bacteria, foreign
• Immune system helps to prevent infections and keeps body
• The three main components of the immune system are
1) Antibodies, 2) Inflammatory cells, and 3) Inflammatory
Immune System of the Body cont…
• Antibodies are the specific proteins created by the immune
system to identify and bind to foreign substances (antigens).
• Antibodies are also called as immunoglobulins IgG, IgM, IgA,
IgD and Ig E.
• Antibodies are specifically targeted against particular
antigens. Immunoglobulins (Ig) destroy antigen by attaching
to its surface, thereby making it easier for other immune
cells to destroy it.
• Antibodies are created and secreted by B cells. For eg. IgM
and IgG are essential to fight the infection quickly,
• IgE is involved in allergic response.