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9 Common Allergy Triggers

An allergen is an otherwise harmless substance that the immune system mistakes as being harmful. There are many types of allergens and conditions caused by them. Some people are allergic to lots of things. Some people are allergic to only one thing or to very few things. What a person is allergic to is determined by many different factors, including the environment, a person’s genes, and the way the immune system works.

Once an allergy has been identified, your healthcare provider may recommend medications or therapies to control symptoms. The next step is to decrease or eliminate exposure to the allergen. This is called environmental control. Evidence shows that allergy and asthma symptoms may improve over time if the recommended environmental control changes are made.

Here are the nine most common types of allergens.

Allergy image Animals
Exposure to animal dander (dead skin that is continually shed), as well as animal urine and saliva, causes human allergic reactions to animals. These reactions can make asthma, rhinitis, and eczema symptoms worse in some people.

The dander, urine, and saliva of feathered or furry animals, such as cats, dogs, birds, and rodents, can cause allergy symptoms. Exposure to other warmblooded animals, such as horses or cattle, or to products made with feathers or down may also cause allergy symptoms.

Allergy image Cockroaches
Cockroach allergies are remarkably common. Cockroach allergies may be dangerous to people with asthma, as exposure may cause severe attacks in over half of those diagnosed. Even if you’ve never seen a cockroach in your home, the allergen may be present. It is not necessarily a reflection of the cleanliness of your home. Cockroaches live in walls and other places you cannot see or easily clean. Cockroaches can congregate wherever food and warmth are present. This can include restaurants, hospitals, and bakeries, as well as upscale urban dwellings.

Allergy image Dust Mites
These are microscopic animals, too small to be seen with the naked eye, that feed on human skin scales. They persist in bedding, carpets, stuffed furniture, old clothing, and stuffed toys. Dust mites are most common in humid climates. If droppings of dust mites are inhaled or come in contact with the skin, they may cause allergic symptoms and aggravate asthma and eczema.

Allergy image Stinging Insects
Although less common than pollen allergy, insect venom allergy is anything but trivial – it can be life threatening. The primary offenders are most often insects that sting rather than those that bite. Stinging insects of concern include yellow jackets, hornets, wasps, bees, and ants.

Allergy image Food
An allergic reaction to a food is an unpleasant reaction caused by the immune system overreacting to a food. For those who are allergic, it is important to diagnose the allergy and identify the food so that serious, and even life-threatening, reactions can be avoided. The most common food allergies are eggs, peanuts, milk, tree nuts, fish, shellfish, soy, and wheat.

Allergy image Latex
A natural rubber made from the sap of a tree, latex can be found in many items, including bicycle and wheelchair tires, toys, some balloons, examining gloves, household gloves, surgical tubing, rubber bands, and condoms. The major exposure of concern is to powdered latex gloves, because latex sticks to the powder and becomes airborne when these gloves are put on, taken off, or snapped.

When someone is allergic to latex, that person is actually allergic to one or more proteins found in the sap from the rubber tree. Interestingly, these proteins – or ones very similar – can be found in banana, kiwi, avocado, potato, strawberries, peaches, and chestnuts. Therefore, people who are allergic to latex may have cross-reactions to these foods.

Allergy image Medication
Allergies to medications are complicated because they can be caused by many different medications, resulting in a wide variety of signs and symptoms that may affect various organs or parts of the body. However, one characteristic of all drug allergies is that similar symptoms will occur every time soon after the offending medicine is taken. Penicillin and other antibiotics are the medicines that most commonly cause allergic reactions.

Allergy image Mold
Many types of molds live in our environment. Mold grows in indoor and outdoor areas that are warm, dark, or moist. Molds reproduce and grow by sending tiny spores into the air. Inhaled spores cause allergy and asthma symptoms.

Allergy image Pollen
When pollen from trees, grasses, and weeds is inhaled, it can cause allergy and asthma symptoms. Pollen may travel many miles in the wind, so trees, grasses, and weeds beyond your immediate area can cause allergy and asthma symptoms. Pollen allergies are often seasonal, and allergy and asthma symptoms occur when the amount of pollen in the air is high.


Source: National Jewish Health,

This article was originally published in Coping® with Allergies & Asthma magazine, September/October 2011.