The Connection Between Allergies and Asthma
Because ]]>asthma]]> and allergies are so common and frequently occur together, most parents may want to know about preventing or avoiding these conditions.
“Allergen” is the word that doctors use to describe a substance in the environment to which our bodies may react with an allergic or asthmatic reaction. Common allergens include pollen, mold, dust mites, latex, ]]>certain foods]]>, ]]>bee stings]]>, ]]>certain plants]]>, and medicines.
We are all exposed to at least some allergens all the time. But, many of us can encounter these troublemakers without experiencing any symptoms at all. For most people, their body simply does not react to allergens. However, for millions of people, an excessive immune response to allergens triggers a cascade of unpleasant symptoms. These symptoms are sometimes mild, but they can be severe, or rarely, even fatal. Allergic symptoms most commonly include: itching of the eyes, throat, or skin; sneezing; nasal congestion; coughing; wheezing; or rash.
Typically, allergic substances enter the body in one or more of the following ways:
- Absorption through the skin (eg, ]]>poison ivy]]>)
- Inhalation through the mouth or nose (eg, pollen, dust mites)
- Ingestion (eg, foods, medicines)
- Injection (eg, insect sting)
Asthma is a condition in which the lungs react to some kind of irritation by producing mucous and inflammation along your breathing pathway. This reaction may occur moments after exposure to an irritant or after several hours have passed. Allergy is a common cause of asthmatic reactions, but similar symptoms can be produced by non-allergen sources (eg, irritant chemicals, viral infections, or other lung irritants). Asthma is usually controllable with treatment. In between “attacks,” or after treatment, the lungs return almost completely to normal. An asthma episode usually includes difficulty breathing, shortness of breath, cough, or other respiratory symptoms.
Exposure to tobacco smoke may trigger asthma in children as smoke is an irritant. Other triggers include exercise, cold air, viral infections, and allergens. The allergens that most commonly cause an asthma episode are dust mites, mold, pollen, and animal dander. Food allergies can also trigger an asthma episode in some people. Foods like shellfish and peanuts can be asthma triggers.
The Allergy-Asthma Connection
It is possible for your children to have allergies but not asthma, or to have asthma without allergies. But, the two conditions often occur together. ]]>Eczema]]> and ]]>hay fever]]> are common allergies associated with asthma.
For some people, the connection between these conditions lies in the similar biologic responses they provoke to what are, for the most part, harmless environmental triggers. If you have allergies and/or asthma, your body is attempting to protect itself from substances it perceives to be dangerous. Unfortunately, this protective reaction triggers the release of body chemicals that cause results like sneezing, congestion, itchy red eyes, skin rash and/or wheezing, shortness of breath, and cough. With allergic asthma, the allergic reaction is confined to the airways, whereas other forms of allergy may affect the skin, eyes, or ears.
Putting Knowledge Into Action
You cannot change your child's genetics, but you can do a number of things to safeguard your home and family against allergies and asthma. While developing allergies and/or asthma may be inevitable for some, following these tips may lessen the severity and frequency of episodes for people who are at high risk:
- Control exposure to smoke—Do not smoke at all. But, if you must smoke do so outside. Never smoke in a car that children ride in, even if your child is not in the car at the time. Wood smoke may also be an asthma risk; avoid wood heating. It may also be wise to assure that gas heaters and stoves are vented to the outside. These appliances produce combustion products that can irritate the lungs.
- Control exposure to pets—This is often debated as the evidence is inconsistent. In some studies, exposure to pets at a young age was associated with less risk of allergies.
- Control exposure to dust mites—Dust mites are microscopic creatures that are found in large quantities in your home. They tend to live in bedding, but are far too small to be seen. Strategies to reduce exposure to mites include:
- Wash all linens in hot water every seven days.
- Place zippered, plastic covers on pillows and mattresses. Although this often recommended, there is little evidence that this actually helps.
- Vacuum carpeting and upholstered furniture frequently using a vacuum cleaner with a “HEPA” filter.
- Keep indoor relative humidity below 50%.
There are other exposures you might want to avoid. Be aware that latex paints, chipboard furniture, and some rugs may release certain chemicals that can cause wheezing in children. If you can, choose to live away from busy highways. This will reduce any risk from automobile and truck exhaust.
Other sources of allergies include cockroaches, rodents, and mold. Careful cleaning of bathrooms and repairing leaky pipes can help reduce mold from growing.
Food is an important trigger for some children. Breastfeeding may help reduce the incidence of allergies, as well as asthma.
Knowing the underlying types, causes, and triggers of both asthma and allergies is the foundation of putting effective prevention and treatment strategies into action.
American Academy of Allergy, Asthma, and Immunology
Asthma and Allergy Foundation of America
Allergy Asthma Information Association
Calgary Allergy Network
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Last reviewed July 2010 by ]]>Brian Randall, MD]]>
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
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