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The allergy-asthma connection

If you or a loved one suffers from allergies, asthma or both, you may realize that the conditions have a lot in common, sharing triggers, symptoms and even treatments. Nearly all children and half the adults who suffer from asthma also have allergies. And if that weren’t enough to illustrate the allergy and asthma link, studies have shown that if your family has a history of allergies, you’ll be more likely to develop asthma.

An allergy occurs when your immune system overreacts to a substance that’s normally harmless in others, such as dust, pollen, mold or pet dander. This overreaction causes your body to release histamines and other types of chemicals to fight off allergens, or the substances that trigger the allergic response. This produces the symptoms typical of allergies: sneezing, wheezing, coughing and itching.

Asthma, on the other hand, results from inflammation of your lungs’ main air passages. As your chest tightens and airways narrow, you have trouble breathing, shortness of breath, coughing and wheezing. Asthma symptoms may be induced by a respiratory infection; exercise; acid-reflux disease; or exposure to cold air, pollution, perfume or tobacco smoke. But for most people with asthma, the primary trigger is an allergic reaction.

First one, then the other

Because the triggers behind allergic and asthmatic reactions are often the same, experts believe the two conditions are simply different stages of the same illness. Many children with asthma have allergies first, such as eczema and hay fever, before the condition progresses to asthma. Children and adults with milder allergies may not yet have asthma, but are at increased risk for developing it.

Although there’s no cure for either allergies or asthma, you can control them with proper treatment, including taking medication and aggressively avoiding allergens. Medications like corticosteroids and leukotriene modifiers are used to treat both allergies and asthma by reducing inflammation. Antihistamines often help allergies but not asthma. And bronchodilators open congested airways that occur with asthma but aren’t used for allergies. Immunotherapy, or allergy shots, can desensitize a person to certain allergens—and may reduce the risk for developing asthma later in life.

Can allergies and asthma be prevented?

Physicians are increasingly promoting measures to help delay, prevent or reduce the risk for developing allergies and asthma in children such as:

  • breastfeeding newborns for at least six months
  • eliminating exposure to tobacco smoke
  • avoiding group day care for very young children to limit respiratory infections
  • limiting exposure to dust mites by reducing dust-collecting clutter, avoiding carpets, encasing pillows and mattresses in plastic covers and washing bedding in hot water frequently

Interestingly, research found that exposure at a young age to cats and dogs may help protect against allergies.

Allergy shots and a newly approved medication, known as anti-IgE, which stops an allergic reaction before it starts, may help prevent allergies and subsequent asthma. If you have allergies or asthma or if they run in your family, talk to your healthcare provider about finding the best way to keep you breathing easy.