Other sources include bees, mosquitoes, chemicals, perfumes, makeup, over-the-counter medication, and antibiotics.
Eight foods account for 90 percent of all food-allergic reactions. They are milk, egg, peanut, tree nuts, fish, shellfish, soy, and wheat.
Some of these allergens may be outgrown, but others, such as peanut and shellfish, will remain lifelong allergies. Substitute foods are almost always available. Other common food offenders are chocolate, pork, and berries.
An individual may be allergic to the gluten in wheat, rye, and oats, and products made from those grains.
Allergens also may affect the respiratory tract, bringing on sneezing, coughing, and difficulty breathing. The allergens, or protein molecules, that are involved are pollens, dust, smoke, perfumes, and various airborne chemicals.
A person also can become allergic to specific types of mold by inhaling the spores consistently. In the nose, the mold spores trigger a reaction in cells of the tissues beneath the mucous membranes that line the nasal passages.
This results in the symptoms of an allergy. Because they are small, mold spores can evade the natural protective mechanisms of the nose and upper respiratory tract and reach the lungs. Here they bring on an allergic reaction in these tissues that resemble asthma.
Less frequently, inhaling mold spores can result in skin lesions similar to those of eczema or chronic hives. In all but the very warmest areas of the United States, molds are seasonal allergens, occurring from spring into late fall.
But unlike pollens, molds do not disappear with the killing frosts of autumn. Actually, frost may help increase the activity of molds, which thrive on dying vegetation produced by cold temperatures.
House dust and animal hair (especially cat and dog hair) are also responsible for respiratory allergies in many people. Dust allergies are usually the responsibility of dust mites, minute arthropods that live in the dust and thrive off of dead skin cells.
Asthma attacks are often triggered by contact with pet dander and dust mite feces or body parts. Symptoms of dust allergy are usually most severe in the spring and fall, and tend to subside in the summer when air conditioners bring down the humidity level in the homes.
Mites are unable to drink water and must get fluids by absorbing them from the air. When the humidity level is low they begin to die off.
Exposure to man-made chemicals can also cause allergic reactions.
An example of respiratory allergy caused by man-made allergens is “meat wrappers’ asthma”
This results from fumes of the price-label adhesive on the poly-vinyl chloride film used to package foods.
The fumes are produced when the price label is cut on a hot wire. When the fumes are inhaled, the result is burning eyes, sore throat, wheezing and shortness of breath, upset stomach, and other complaints.
Studies have shown that exposure to these fumes for as little as five minutes have produced airway obstruction in food packagers.
Another source of respiratory allergy is the photochemical smog produced by motor vehicle exhaust in large cities. Smog is composed of oxides of nitrogen, hydrocarbons, and other chemicals activated by the energy of sunlight. When inhaled the smog has been found to impair the normal function of membranes in the lungs.
Meicines and drugs, such as penicillin can cause allergic reactions. Estimates of the incidence of allergy among those receiving penicillin range from one to ten percent.
The National Institutes of Health has calculated that just three common drugs—penicillin, sulfonamides, and aspirin—account for as much as 90 percent of all allergic drug reactions.
Allergic reactions to medications, drugs and inoculations include asthmatic symptoms, skin rash, shock, and other symptoms. Scientists theorize that chemicals in certain drugs probably combine with protein molecules in the patient’s body to form a new substance that is the true allergen.
Insect stings cause serious allergic reactions in about four of every 1,000 persons stung by bees, fire ants, yellow jackets, wasps, or hornets. A single sting to a sensitive person may lead to an anaphylactic response characterized by a serious drop in blood pressure, shock, and possibly death.
There are more than 50 reported fatalities each year, and experts suspect that other deaths occur as a result of insect stings but are listed as heart attacks, stroke, or convulsions.
Recently physicians have found that using pure insect venom produces a reaction that determines whether a person is allergic to the sting. Scientists also have isolated the major allergens in an insect venom for use in diagnosing and treating patients who are particularly sensitive to stings.
These advances have led to an increasing ability to test for allergies to insect venom.You may like: