Allergies 101

Understanding Allergies

  • Introduction
  • What are Allergens
    1. An allergen (also referred to as an antigen) is any substance alive or dead that can cause a reaction in the human body. Upon gaining access into the body, the allergen can cause hypersensitive reaction type I. This body responds with an immunoglobulin E (IgE) response. The best example of such reaction is described as
      1. (atopic) hereditary reaction asthma, hay fever, and certain skin irritation.
      2. Reaction to parasitic infections.

Patients show a range of responses to such reaction depending on the patient’s immune system.

  1. Types of allergic reactions Type I, Type II, Type III and type IV
  • Type I reactions, otherwise known as immediate or anaphylactic reactions, take place when mast cells and basophils release histamine and other mediators. The reaction may involve the skin, eyes, nasopharynx, bronchopulmonary tissues and gastrointestinal tract. Often the reaction will only take place 15 – 30 minutes after exposure of the antigen, however at times there may be a delayed onset of 10 – 12 hours.
  • Type II reactions, also known at cytotoxic hypersensitivity, involve immunoglobin G or M antibodies bound to cell surface antigens. The reaction has the potential to affect several organs and tissues. The reaction time usually only takes minutes, often times it may take hours.
  • Type III reactions, otherwise known as immune complex hypersensitivity, involve antigen-antibody immune complexes that deposit in postcapillary venules. The reaction involves organs including: skin, kidneys, lungs, blood vessels, joints and others. The reaction time is 3 – 10 hours after exposure.
  • Type IV reactions, also known as cell mediated or delayed type hypersensitivity, are mediated by T cells as opposed to antibodies. The reaction time is 48 – 72 hours and will appear as eczema.
    1. True allergies and false allergies
  • Sources of allergen (antigens)
    1. Allergens stemming from food such as eggs, dairy products, peanuts, seafood and shellfish
  • Allergens will cross the gastrointestinal lining and enter the bloodstream after which they will be able to travel to target organs and trigger allergic reactions. The reaction time is anywhere between a couple minutes and an hour of ingesting the food. Initial symptoms include an itchy mouth and difficulty swallowing and breathing. During the digestion process of the food symptoms including nausea, vomiting, diarrhea and abdominal pain may occur. Other symptoms include hives, eczema and asthma. As the allergens travel through the bloodstream they have the potential to cause lightheadedness, weakness and anaphylaxis.
    1. Allergens stemming from microorganisms (fungus, bacteria and allergens)
  • Fungal allergies are caused by the spores of a certain fungi. Everyone is exposed to spores however some people have a more severe intolerance than others. Symptoms include: sneezing, runny nose, itchy ears, congested sinuses and dry skin. Fungal allergies may lead to asthma as spores are inhaled into the lungs and may cause inflammation in the air sacs.
    1. Allergens stemming from medication antibiotics, sulfonamides, salicylates
  • Penicillins and sulfonamindes are the main sources of drug allergic reactions. The reaction takes place when the immune system is threatened by the antibiotic and therefore releases chemicals. Symptoms include: itchy or swollen skin, rash, hives and blisters in the mouth. More serious symptoms include: fever, breathing problems, swelling of body tissues,
    1. Allergens (airborne) environmental such as dust mite excretion and pollen
  • Symptoms of environmental allergies include: stuffy nose, sneezing, headache, skin rash/hives, diarrhea and frequent urination.
    1. Allergens stemming from animals , Dander of cats, dogs and birds
  • The major cause of allergic reactions to dogs and cats is not the fur but the dander (old skin scales) that is shed into the environment. Symptoms such as itchy and watery eyes, sneezing and sinus problems occur immediately. Also, it does not take a lot of dander to cause a reaction.
    1. Allergens stemming from botanicals.
  • Poison ivy and poison oak are plants that contain a sap called urushiol. When it comes in contact with skin, it initiates an allergic reaction. The reaction results in an itchy rash hours or even days after exposure. The reaction begins with itchy skin but gradually develops into red bumps or oozing blisters.
    1. Allergens stemming from insects such wasps, fire ants, bees.
  • Insect sting reactions result in pain, itching, swelling and redness at the site of the sting. More serious reactions include increased swelling, vomiting and nausea. The most serious reaction is anaphylaxis which may be fatal.
    1. Allergens stemming from chemicals (shampoos, cosmetics, detergents)
  • Often there will be no initial reaction to these products, but repeated use may cause sensitivity to them. Symptoms of chemical allergies include: skin redness, oozing blisters, swelling of the eyes, hives and sun sensitivity.
  • Anaphylaxis Latex, penicillin,
  • Vaccines and immunizations, Flu shots
  • Immediate reactions to vaccines do not happen very often. The reaction will start within minutes of the vaccination. Symptoms include: swelling, itching, cough, wheezing and loss of consciousness. Local reactions may also take place in the hours following the vaccination. The site of vaccination may become inflamed and it may last several days.
  • Asthma, bronchitis
  • For a person with asthma, allergens have the potential to make the airways swollen and full of mucus. Immediate symptoms include: wheezing and short of breath. The most common asthma inducing allergens are pollen and dust mites.
  • Eczema
  • Eczema is a skin rash that causes redness and itchiness. The foods that most commonly lead to eczema are: eggs, peanuts, wheat and milk. Eczema can also be caused by stress and airborne allergens.
  • Hyper activities in children
  • Consuming foods that one is allergic to have an effect on one’s digestive system. Changes in the gut can results in changes within the nervous system and therefore cause neurological symptoms. Some of the foods which most commonly cause ADHD symptoms include: wheat, food colouring and milk.
  • Tourette’s syndrome
  • Colitis
  • Allergic colitis takes place during infancy and is when the baby has problems eating, gas, diarrhea and blood in the stool. The baby may be allergic to cow’s milk. The protein in milk initiates a reaction in the body that irritates the colon.
  • Anti allergies diet ?
  • Anti allergies treatment ?
  • Anti allergies intravenous treatment ?
  • Conclusion