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What is allergy?
Allergy is a physiological reaction caused when the immune system mistakenly identifies a normally harmless substance as damaging to the body. Normally, the human body defends itself against harmful substances such as viruses or bacteria, but sometimes the defenses aggressively attack usually innocuous substances such as dust, mold, or pollen.The immune system generates large amounts of the antibodies called immunoglobin E (IgE), or immunoglobin G (IgG) a complex chemical weapon, to attack and destroy the supposed enemy. Each IgE antibody specifically targets a particular allergen - the substance that causes the allergy. In this disease-fighting process, inflammatory chemicals like histamines, cytokines, and leukotrienes are released or produced, and some unpleasant (and, in extreme cases, life-threatening) symptoms may be experienced by an allergy-prone person.
Causes, incidence, and risk factors
Allergies are relatively common. Both genetics and environmental factors play a role. Allergy is caused by an oversensitive immune system, which leads to a misdirected immune response. The immune system normally protects the body against harmful substances, such as bacteria and viruses. It reacts to substances (allergens) that are generally harmless and in most people do not cause a problem. But in a person with allergies, the immune response is oversensitive. When it recognizes an allergen, it releases chemicals, such as histamines.
This causes itching, swelling, mucus production, muscle spasms, hives, rashes, and other symptoms, which vary from person to person. What part of the body is contacted by the allergen plays a role in the symptoms you develop. For example, allergens that are breathed in often cause a stuffy nose, itchy nose and throat, mucus production, cough, or wheezing. A food allergen can cause nausea, vomiting, abdominal pain, cramping, diarrhea, or a severe, life-threatening reaction. Allergies to plants often cause a skin rash. Drug allergies usually involve the whole body and can lead to a variety of symptoms. Some medical conditions, such as eczema and asthma, are linked to allergies. Common allergens include pollen, mold, pet dander, and dust. Food and drug allergies are common. Allergic reactions can also be caused by insect bites, jewelry, cosmetics, and other substances. Some people have allergy-like reactions to hot or cold temperatures, sunlight, or other physical stimuli. Sometimes, friction (rubbing or vigorously stroking the skin) will cause symptoms.
What are allergic reactions?
An allergic reaction may occur anywhere in the body, in the skin, eyes, lining of the stomach, nose, sinuses, throat, and lungs - places where immune system cells are located to fight off invaders that are inhaled, swallowed, or come in contact with the skin. Reactions may result in:
*rhinitis - nasal stuffiness, sneezing, nasal itching, nasal discharge, itching in ears or roof of mouth
*allergic conjunctivitis - red, itchy, watery eyes
*atopic dermatitis - red, itchy, dry skin
*urticaria - hives or itchy welts
*contact dermatitis - itchy rash
*asthma (airway problems such as shortness of breath, coughing, wheezing)
What causes allergic reactions?
Although hundreds of ordinary substances could trigger allergic reactions, the most common triggers - called allergens - include the following: pollen, molds, house dust, dust mites and their waste, animal protein (dander, urine, oil from skin)
industrial chemicals, foods, medicines, feathers, insect stings, cockroaches and their waste
Who is affected by allergy?
affect anyone, regardless of age, gender, race, or socioeconomic status. Generally, allergies are more common in children. However, a first-time occurrence can happen at any age, or recur after many years of remission.There is a tendency for allergies to occur in families, although the exact genetic factors that cause it are not yet understood. In susceptible people, factors such as hormones, stress, smoke, perfume, or other environmental irritants may also play a role. Often, the symptoms of allergies develop gradually over a period of time. Allergy sufferers may become so accustomed to chronic symptoms such as sneezing, nasal congestion, or wheezing, that they do not consider their symptoms to be unusual. Yet, with the help of an allergist, these symptoms can usually be prevented or controlled and quality of life greatly improved.
Allergies and Intolerances
The term adverse reaction is used to describe health problems linked to food. Food allergy and food intolerance are two types of adverse food reactions (food-borne illnesses caused by bacterial, viral, or other forms of contamination are also adverse reactions). A food allergy is said to exist when the health problem is linked to a malfunction of the immune system. It is believed that this malfunctioning occurs when the body identifies a food protein (allergen) as a harmful substance. Food intolerance occurs when the underlying problem causing the adverse reaction is not related to a malfunction of the immune system. One example of a food intolerance is lactose intolerance, a condition affecting people who cannot digest milk due to a deficiency of the enzyme lactase, which breaks down milk sugar (lactose).
Diagnostic Laboratories Test
The latest exacting technologies in laboratory medicine re now available to measure, from small blood samples, our immune system response to over 192 food and almost 64 different inhalant allergens. The actual levels of IgE and IgG antibodies against these individual allergens can be precisely measured. This Diagnostic Laboratories allergy test will help you discover with ease what you need to avoid or what you can include in your diet and environment to minimize allergic reactions and allow your body the time to rest and heal.
Possible Symptoms Associated with Food Allergies
Food intolerance is often put into the same category as food allergy, even though there may be an entirely different mechanism involved. In these cases, the digestive tract reacts to a specific part of the food; for example, the protein or the sugar in a specific food. The digestive system rebels, resulting in gas, bloating, upset stomach, diarrhea, nausea, or vomiting. Many times, these responses are due to eating food contaminated with bacteria, rather than a true food allergy. In other cases, the child's reaction is due to an underlying digestive disorder such as irritable bowel syndrome, which is a chronic condition that is often triggered by specific types of food.
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