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Allergies
Allergies worldwide are on the rise. Indoor and outdoor pollution, new substances, improved hygienic conditions, and stressful lifestyles are all playing a role in the surge in allergies. Wherever we live, we may be allergic to a range of substances and products. As our lives have become more complex, so have our allergies.
An allergy is an abnormal reaction to an ordinarily harmless substance called an allergen. An allergy produces an imbalance in the immune system. We talk of "hypersensitivity" to describe the way the body overreacts to certain substances, called ‘allergens’. When an allergen, such as pollen, is absorbed into the body of an allergic person, that person’s immune system views the allergen as an invader and a chain reaction is initiated and body produces antibodies (IgE) and releases histamines, one of the substances responsible for the symptoms of the allergy.
The major signs of an allergy are respiratory problems (rhinitis, asthma, etc.), skin problems (eczema, hives, etc.) and digestive problems (vomiting, diarrhoea, etc.).
Our genetic inheritance is very important in terms of allergies. A child whose parents have a history of allergies runs a 30% risk of developing an allergy him or herself. If both mother and father suffer from allergies, the risk is even greater (50 to 60%). And this risk is higher still if both parents suffer from the same allergy (asthma, eczema, etc.). In several cases, therefore, it is possible to determine which children will be at risk of allergies before the birth.
People can be allergic to one or several allergens. The most common include pollens, molds, dust mites, animal dander (dead skin flakes from animals with fur); foods; medications; cockroach droppings and insect stings.
Allergic individuals can exhibit a variety of reactions depending on the allergen and the way it was absorbed into the body.
1. Seasonal allergic rhinitis sometimes called "hay fever" is caused by an allergy to the pollen of trees, grasses, weeds or mold spores. The sufferer has spells of sneezing, itching and watery eyes, runny nose, burning palate and throat. Seasonal allergies also can trigger asthma.
2. Allergic rhinitis is a general term used to apply to anyone who has symptoms of nasal obstruction, sneezing and a runny nose due to allergies. This may be a seasonal problem as with hay fever, or it may be a year-round problem caused by indoor allergens such as dust mite droppings, animal dander, cockroach droppings or indoor molds. Frequently, this problem is complicated by sinusitis.
3. Eczema or atopic dermatitis is a non-contagious, itchy rash that often occurs on the hands, arms, legs and neck, although it can cover the entire body. This condition is frequently associated with allergies, and substances to which a person is sensitive may aggravate it.
Immunotherapy, or "allergy shots", is recommended for patients with moderate to severe allergy symptoms throughout most of the year, who do not respond adequately to medications, and whose symptoms are triggered by an allergen that is not easily avoided, such as pollens or house dust mites. Immunotherapy involves the injection of allergenic extracts (tiny amounts of allergens) that are given over a period of 3-5 years. By gradually increasing the amount of extract, tolerance to the offending allergen will increase, and the patient’s symptoms will be relieved.
Measures can be taken as soon as a child is born to prevent or limit the allergies from which the baby might suffer. As allergies are linked to the environment and lifestyle of the sufferer, it is possible to delay and even prevent medical symptoms by protecting the baby from early and repeated contact with the main allergens.
People with allergies have an inherited, genetic tendency to produce IgE, the allergic antibody, to many different substances such as seasonal allergens, (trees, grasses, weeds) or year-round allergens (dust mites, pet dander). When a person with allergies moves to another location, exposure to different allergens in the new location will likely result in a new set of allergy triggers, thereby trading one set of symptoms for another. In some cases, the benefits of a change in location may outweigh the negative aspects. Before making a move to "get away from your allergies" consult with your allergist. Also, when contemplating a move, if possible, check out the new environment by visiting there for two to four weeks (or more) to see if your symptoms improve. Keep in mind it may take months or years to become allergic to a new allergen i.e., tree, grass or weed species. Seasonal allergy sufferers may be able to find temporary relief by taking a vacation during the height of the pollen season to a more pollen-free environment such as near large bodies of water.
In some cases, it is dangerous to ignore allergy symptoms. Severe and untreated hay fever may lead to asthma, sinusitis, and other serious conditions. Allergic dermatitis or eczema can spread to secondary infections if they are not treated properly, and untreated asthma can lead to chronic symptoms. Early detection and treatment of all allergic diseases is important.
The tendency to have allergies is genetically inherited. Thus, instead of a cure, patients should work with their allergist to keep their allergies under control. Successful treatment of allergies includes early detection, proper usage of medications and simple allergen avoidance techniques.
Breastfeeding provides your baby with added protection against allergies. By drinking its mother’s milk, your baby won’t be exposed to foreign proteins early on. Moreover, breast milk is an important source of immunoglobulins which restrict the penetration of allergens via the intestinal mucous and which help the baby to fight off infection
Animals with fur or feathers (cats, dogs, hamsters, guinea pigs, etc.) are one of the major sources of allergens (from their saliva, urine, dander and excrement, etc.). The majority of people become sensitized to contact with their own pet(s). This is why pets are strongly discouraged, in particular during the sensitisation phase.
The symptoms observed can be: • digestive problems (diarrhoea, vomiting, colic) • skin problems (eczema, hives) • respiratory problems (asthma, repetitive bronchitis, rhinitis and in particular hayfever, etc.) • others: repetitive otitis, conjunctivitis, etc.
What are the main allergens to be avoided for children at risk of or already suffering from allergies?
The substances you should avoid are the following: A. IN THE SURROUNDING ENVIRONMENT: • house-dust mites B. IN FOOD: • milk and dairy products
• mould
• animal hair and feathers
• pollen
• cigarette smoke and other irritants
• eggs
• fish
• peanuts
• exotic fruits (kiwi, papaya, etc.)
• dried fruits and nuts (walnuts, hazelnuts, almonds, etc.)
Like all other allergic diseases, drug allergy is caused by an inappropriate reaction of the immune system to a chemical substance in the drug. The allergic response can be triggered by the drug itself but also by one of the compounds into which the drug is metabolised in the body (most drugs are metabolised).
Anaphylaxis is the most dramatic expression of allergy. In an anaphylactic attack, symptoms may develop within minutes after coming into contact with the allergen and may rapidly become very severe, threatening vital body functions such as respiration and blood circulation. Most anaphylactic attacks are triggered by food allergens, insect venoms, drugs and latex.
Allergen Avoidance
Immunotherapy:
This treatment aims to make your immune system tolerant to the allergen causing your problems. This would prevent you from developing allergy symptoms when you come into contact with the allergen in the environment after treatment.Drug Treatment:
Anti-allergy drugs can be grouped into two categories:• Symptom relieving drugs which are useful during acute allergic attacks. Examples of such drugs are antihistamines, useful for the treatment of allergic rhinitis or allergic conjunctivitis or episodes of urticaria, or bronchodilator medications that helps to reverse the narrowing of the bronchi during asthma attacks.
• Disease controller drugs which cannot relieve an acute flare-up of the disease but prevent acute exacerbations if administered regularly and for a longer period of time. A typical example of this type of drug are the corticosteroids. Controller drugs have strong anti-inflammatory properties and can calm down the immune conflict triggered in our body by contact with an allergen. These drugs take days or even weeks to become fully effective, this is why they cannot be used to treat the symptoms during acute flare-ups.
