Call today for an appointment (925) 846-5100

What Are Allergies?

Allergies represent an unusually reactive response of the immune system.  Substances that usually cause no reaction can trigger sneezing, wheezing, coughing and itching in people with allergic illnesses.  Allergies are not only annoying, but may be linked to serious diseases such as sinusitis, rhinitis, asthma and other chronic diseases of the respiratory tract.  Allergic reactions can be severe and even fatal. Fortunately, with proper management, allergic diseases can be controlled.  Under the care of an Allergist, people with allergies lead normal, productive and healthy lives.

What Causes Allergies?

The substances that cause allergic disease in people are known as allergens or  “Antigens.” These are protein particles such as pollen, animal dander and other substances which come into contact with our bodies.  If the particles cause an allergic reaction, the substance is considered an “allergen.”  Allergens can get into our body in a variety of ways:

  • Inhalation (through the mouth and nose).  Examples of some airborne allergens include substances, such as pollen from trees, grasses and weeds; house dust, which may include particles from mited, mold spores; dander from cats, dogs and other animals; and particles from substances such as latex. 
  • Ingestion (food substances).  Common culprits include shrimp, peanuts and dairy products. 
  • Injectables (medications). Such as medications delivered by needle like penicillin or other injectable drugs, and venom from insect stings and bites. 
  • Contact (through the skin).  Poison ivy, sumac and oak and latex are examples of allergens that cause reactions on contact .

Are Allergies Hereditary?

Yes, the capacity to become allergic is an inherited characteristic, much like baldness, height and eye color. However, being born with the genetic predisposition to become allergic does not guarantee that you will become allergic to any specific allergen.  Factors that affect your chance of developing an allergic sensitivity to a substance include:

  • The specific genes you inherited from your parents.
  • The degree of exposure to the allergen to which you may become allergic.
  • The length of exposure to the allergen to which you may become allergic.

A person born with a propensity to become allergic to cow's milk, for example, may show allergic symptoms several months after birth,  while a genetic tendency toward a cat dander allergy could take three to four years of exposure or longer before symptoms are experienced.  People with allergic tendencies may also become allergic to new and different environmental substances as they age.

On the other hand, poison ivy allergy (contact dermatitis) is an example of an allergy in which hereditary background does not play a part. The person with poison ivy allergy first has to be exposed to the oil from the plant. This usually occurs during youth, when a rash does not always appear. However, the first exposure may sensitize or cause the person to become allergic and, when subsequent exposure takes place, a contact dermatitis rash appears and can be quite severe. Many plants are capable of producing this type of rash. Substances other than plants, such as dyes, metals, and chemicals in deodorants and cosmetics, can also cause a similar dermatitis.

Copyright © 2008-2010 Dr. Beth Cowan