Everything You Need to Know About Allergies

What Are Allergies?

Allergies are an overreaction of the immune system to substances that usually cause no reaction in most individuals. These substances can trigger sneezing, wheezing, coughing and itching. Some allergies have been linked to a variety of common and serious chronic respiratory illnesses (such as sinusitis and asthma). Additionally, allergic reactions can be severe and even fatal. However, with proper management, allergies can be controlled, allowing their sufferers to lead normal, productive lives.

Common Allergies

• Allergic rhinitis (hay fever or "indoor/outdoor," "seasonal," "perennial" or "nasal" allergies) includes these symptoms: nasal stuffiness, sneezing, clear discharge, and itching of the roof of the mouth and/or ears in addition to the nose.

• Asthma symptoms triggered by an allergic reaction include coughing, wheezing, shortness of breath or rapid breathing, chest tightness, occasional fatigue and slight chest pain.

• Food allergies are most prevalent in very young children and frequently outgrown. Symptoms may include itching or swelling of lips or tongue; tightness of the throat accompanied by hoarseness; nausea and vomiting; diarrhea; occasionally chest tightness and wheezing; itching of the eyes; decreased blood pressure or loss of consciousness and anaphylaxis.
  Anaphylaxis is an extreme response to an allergy that is a medical emergency requiring immediate attention. Symptoms include generalized warmth or flush; tingling of palms, soles of feet or lips; light-headedness; bloating and chest tightness. These symptoms can progress into seizures, cardiac arrhythmia, shock and respiratory distress. Possible causes: medications, vaccines, food, latex, and insect stings and bites.

• Drug allergies can cause anaphylaxis; even those who do not have life-threatening symptoms initially may progress to a life-threatening reaction.

• Latex allergies represent a response to the proteins in natural, latex rubber. People at risk include healthcare workers, patients having multiple surgeries and rubber-industry workers. Symptoms include hand dermatitis, eczema and hives; sneezing and other respiratory distress; and lower respiratory problems including coughing, wheezing and shortness of breath.

• Insect Sting/Bite allergy symptoms include pain, itching and swelling at the sting site or over a larger area and can cause anaphylaxis. Insects to be aware of include bees, hornets, wasps, yellow jackets, and fire and harvest ants.

• Urticaria (hives, skin allergy) is characterized by the development of itchy, raised white bumps on the skin surrounded by an area of red inflammation. Acute urticaria is often caused by an allergy to foods or medication.

• Atopic Dermatitis (eczema, skin allergy) is a chronic or recurrent inflammatory skin disease characterized by lesions, scaling and flaking; it is sometimes called eczema. In children, it may be aggravated by an allergy or irritant.

• Contact Dermatitis (skin allergy), characterized by skin inflammation, is one of the most common skin diseases in adults. It results from direct skin contact with an outside substance. There are currently about 3,000 known contact allergens.

• Allergic Conjunctivitis (eye allergy) is characterized by itchy, watery eyes and lid distress. It is common among those who suffer from other allergies such as atopic dermatitis, allergic rhinitis and asthma.

What Causes Allergies?

The substances that cause allergic disease in people are known as allergens. "Antigens," or protein particles like pollen, food or dander enter our bodies through a variety of ways. If the antigen causes an allergic reaction, that particle is considered an "allergen." These can be:

Inhaled

Plant pollens that are carried by the wind cause most allergies of the nose, eyes and lungs. These plants (including certain weeds, trees and grasses) are natural pollutants produced at various times of the year when their small, inconspicuous flowers discharge literally billions of pollen particles.

Unlike wind-pollinated plants, conspicuous wild flowers or flowers grown in most residential gardens are pollinated by bees, wasps, and other insects and therefore are not widely capable of producing allergic rhinitis.

Another culprit: house dust that can include dust mite particles, mold spores, cat and dog dander.

Ingested

Frequent culprits include shrimp, peanuts and other nuts.

Injected

Such as medications delivered by needle like penicillin or other injectable drugs; venom from insect stings and bites.

Absorbed

Plants such as poison ivy, sumac and oak and latex are examples.

Genetics

Like baldness, height and eye color, the capacity to become allergic is an inherited characteristic. But that doesn't make you automatically allergic to specific allergens. Several factors must be present:

• Specific genes acquired from parents.
• Exposure to one or more allergens to which you have a genetically programmed response.
• Degree and length of exposure.

A baby born with the tendency to become allergic to cow's milk, for example, may show allergic symptoms several months after birth. A genetic capability to become allergic to cat dander may take three to four years of cat exposure before the person shows symptoms.

On the other hand, poison ivy allergy (contact dermatitis) is an example of an allergy in which hereditary background does not play a part. Substances other than plants, such as dyes, metals, and chemicals in deodorants and cosmetics, can also cause a similar dermatitis.

Diagnosis

If you break out in hives when a bee stings you, or you sneeze every time you pet a cat, you know what some of your allergens are. But if the pattern is not so obvious, try keeping a record of when, where, and under what circumstances your reactions occur. If the pattern still isn't clear, make an appointment with your doctor. Doctors diagnose allergies in 3 steps:

1. Personal and medical history. Your doctor will ask you questions to get a complete understanding of your symptoms and their possible causes. Bring your notes to help jog your memory. Be ready to answer questions about your family history, the kinds of medicines you take, and your lifestyle at home, school, and work.

2. Physical examination. If your doctor suspects an allergy, he/she will pay special attention to your ears, eyes, nose, throat, chest, and skin during the physical examination. This exam may include a pulmonary function test to detect how well you exhale air from your lungs. You may also need an X-ray of your lungs or sinuses.

3. Tests to determine your allergens. Your doctor may do a skin test, patch test or blood test.

• Skin test. These are generally the most accurate and least expensive way to confirm suspected allergens. There are two types of allergen skin tests. In prick/scratch testing, a small drop of the possible allergen is placed on the skin, followed by lightly pricking or scratching with a needle through the drop. In intra-dermal (under the skin) testing, a very small amount of allergen is injected into the outer layer of skin.
  If you are allergic to the substance, you will develop redness, swelling, and itching at the test site within 20 minutes. You may also see a "wheal" or raised, round area that looks like a hive. Usually, the larger the wheal, the more sensitive you are to the allergen.

• Patch test. This is a good test to determine if you have contact dermatitis. Your doctor will place a small amount of a possible allergen on your skin, cover it with a bandage, and check your reaction after 48 hours. If you develop a rash, you're allergic to the substance.

• Blood tests. Allergen blood tests (also called radioallergosorbent tests [RAST], enzyme-linked immunosorbent assays [ELISA], fluorescent allergosorbent tests [FAST], multiple radioallergosorbent tests [MAST], or radioimmunosorbent tests [RIST]) are sometimes used when people have a skin condition or are taking medicines which interfere with skin testing. Your doctor will take a blood sample and send it to a laboratory. The lab adds the allergen to your blood sample, and then measures the amount of antibodies your blood produces to attack the allergens.

Treatment

Good allergy treatment is based on the results of your allergy tests, your medical history, and the severity of your symptoms. It can include three different treatment strategies: avoidance of allergens, medication and/or immunotherapy (allergy shots).

Avoiding Allergens

The best way to prevent allergy symptoms and minimize your need for allergy medicine is to avoid your allergens as much as possible and to eliminate the source of allergens from your home and other environments.

Medication

While some may find relief with an over-the-counter medicine, such as Claritin, Alavert, or Zyrtec-D, others may prefer a stronger one-a-day prescription tablet, such as Singulair. Ask your doctor for recommendations, but don't mix your meds; following a non-drowsy 24-hour drug with a different p.m. pill could lead to dizziness, increased heartbeat, and nausea. Most important: Take allergy medications as regularly as suggested by a doctor to ward off attacks, rather than just when you're experiencing symptoms.

• Antihistamines and decongestants are the most common medicines used for allergies. Antihistamines help relieve rashes and hives, as well as sneezing, itching, and runny nose. Prescription antihistamines are similar to their non-prescription counterparts, but many of them do not cause drowsiness. Decongestant pills, sprays, and nose drops reduce stuffiness by shrinking swollen nasal membranes.
  Don't use a non-prescription nasal decongestant spray for more than three days in a row since it may cause the swelling and stuffiness in your nose to become worse, even after you stop using it. This is called a "rebound" reaction. If you have asthma, talk with your doctor before taking any non-prescription allergy medicine.

• Eye drops may provide temporary relief from burning or bloodshot eyes. However, only prescription allergy eye drops contain antihistamines that can reduce itching, tearing and swelling.
• Corticosteroid creams or ointments relieve itchiness and stop the spread of rashes. If your rash does not go away after using a non-prescription corticosteroid as directed, see your doctor. Corticosteroid nasal sprays help reduce the inflammation that causes nasal congestion without the risk of the "rebound" effect found in non-prescription nose sprays. Oral Corticosteroids may be prescribed to reduce swelling and stop severe allergic reactions.
• Cromolyn Sodium prevents the inflammation which causes nasal congestion. Because it has few, if any, side effects, cromolyn can be used safely over long periods of time.

• Epinephrine comes in pre-measured, self-injectable containers, and is the only medication which can help during a life-threatening anaphylactic attack. To be effective, epinephrine must be given within minutes of the first sign of serious allergic reaction.

Immunotherapy (Allergy Shots)

When it is not possible to avoid your allergens and treatment with medications alone does not solve the problem, or if you're affected by seasonal allergies for more than three months of the year, allergy shots, also called immunotherapy, may be in order. This involves giving a person increasingly higher doses of their allergen over time. For reasons that we do not completely understand, the person gradually becomes less sensitive to that allergen. Shots can be effective for some people with hay fever, certain animal allergies, and insect stings. ) By changing the immune pathways, immunotherapy may even help prevent the development of other allergies as well as asthma. It is usually not effective for allergies to food, drugs, or feathers, nor is it effective for hives or eczema.>

Prevention

There are some simple strategies you can use to prevent allergies at home, work school, outside and when you travel.

1. Dust to control mites. Dust mites are one of the most common allergens found in homes, according to the American Academy of Allergy, Asthma & Immunology. These microscopic creatures live in beds, carpets, pillows, and upholstered furniture, feeding on our dead skin cells. But it's their droppings that some people are allergic to. By dusting surfaces and washing bedding often, you can control the amount of dust mites in your home. Since getting rid of dust mites completely is difficult, it's best to put a barrier between you and them. Cover your mattress, box spring, comforter, and pillows with special allergy cases, which are woven in such a way that the dust-mite droppings can't get through. (Look for AllerCare products, $10 to $100; bedbathandbeyond.com.)
   
2. Vacuum often. Although cleaning can sometimes trigger allergic reactions, with dust in the air, vacuuming all floors, especially carpets, once or twice a week will reduce surface dust mites. Wear a mask when doing housework and consider leaving for a few hours after you clean to avoid allergens in the air. You can also opt for a vacuum that has an air filter to capture dust. HEPA (high-efficiency particulate air filter) vacuums trap particles and don't spew them back into the air. Also make sure your carpet cleaner contains tannic acid, a chemical that helps destroy dust mites.

1. Reduce pet dander. If you have allergies, you should avoid pets with feathers or fur like birds, dogs and cats. Animal saliva and dead skin, or pet dander, can cause allergic reactions. Additionally, dogs and cats that frolic outdoors can collect pollen in their fur and transport it into your home. If you can't bear to part with your pet, at least keep it out of the bedroom. Especially during hay fever season, bathe your pet as frequently as possible or wipe him down when he comes in from the yard with a premoistened cloth, such as Simple Solution Allergy Relief from Pets ($7; petco.com).
   
2. Protect against pollen. Experts estimate that 35 million Americans suffer from allergies because of airborne pollen, The number one anti-allergy move is to keep triggers at bay, so be sure to leave your windows and doors shut during pollen season. Run the air conditioner on the "recycle" setting, which filters indoor air, trapping any particles that did sneak inside. Also rinse or replace the filter every two weeks to remove dust and keep it running efficiently.
   
3. Clear the air. Almost half of seasonal allergy sufferers are also bothered by irritants such as fragrances and cleaning products. To breathe easier, invest in a HEPA air purifier, which filters out aggravating indoor pollutants. A good pick: Honeywell HEPA Tower Air Purifier ($250; target.com).
   
4. Rethink your bedtime routine. Hopping in the shower in the morning is one way to kick-start your day, but switching to a nighttime routine during the spring and summer can curb your symptoms. You'll wash away the allergens that stick to your hair and face, so they won't rub off on your pillow and irritate your eyes and nose. At the very least, gently clean your eyelids.
   

1. Avoid mold spores. Mold spores grow in moist areas. If you reduce the moisture in the bathroom and kitchen, you will reduce the mold. Fix any leaks inside and outside of your home and clean moldy surfaces. Plants can carry pollen and mold too, so limit the number of houseplants. Dehumidifiers can also help reduce mold.
   
2. Be school savvy. Children in the United States miss about two million school days each year because of allergy symptoms. Parents, teachers and health care providers can work together to help prevent and treat childhood allergies. Monitor the classroom for plants, pets or other items that may carry allergens. Encourage your child to wash his/her hands after playing outside. Investigate treatment options to help your child manage his/her symptoms during the school day.
   
3. Exercise outdoor smarts. Stay inside during peak pollen times, usually between 10:00 a.m. and 4:00 p.m., when humidity is high, and on days with high wind, when dust and pollen are more likely to be in the air. If you do venture out, wear a facemask to limit the amount of pollen you inhale. Shower after spending time outside to wash away pollen that collects on your skin and hair.
   
4. Keep your lawn trimmed. The shorter blades won't trap as much pollen from trees and flowers.
   
5. Fine-tune your fitness routine. You breathe at least twice as fast when you're working out, which means you'll inhale even more allergens if you exercise outdoors. Morning exercisers are hit hardest because airborne allergens peak during the early hours, starting at 4 a.m. and lasting until noon. Because pollen rises as morning dew evaporates, the ideal time for an outdoor workout is mid-afternoon. Where you work out can also matter: Exercising on the beach, an asphalt tennis court, the track at your local high school, or in the swimming pool are better options than working out on a grassy field.
   
6. Run right after it rains. The moisture washes away the pollen for up to several hours. But once the air dries, take cover: The additional moisture generates even more pollen and mold, which can hang around for several days. (Before heading out, check pollen and mold reports on aaaai.org.)
   

1. Slip on shades. Not only do wraparound sunglasses shield you from harmful UV rays, they'll also prevent airborne allergens from getting in your eyes. Another way to ward off symptoms: Use allergy-relieving eyedrops, such as Visine-A, a few hours before heading outside. This will combat histamines, which are the compounds that cause your eyes to water and itch.
   
2. Drink up. Fill up a water bottle or hydration pack to bring on your run, walk, or bike ride. Fluids help thin mucus and hydrate the airways, so you won't get as stuffed up. Use what's left to rinse off any pollen that's on your face and hands.
   
3. Hit the laundry room more frequently. When you get back from a walk or barbecue, take off your shoes and change into a clean set of clothes. Then toss the old ones right into your hamper or laundry so you won't track allergens throughout the house. And wash your sheets once a week on the hot cycle.
   
   A Korean study found that washing linens in 140°F water killed nearly all dust mites, where as warm (104°F) or cold (86°F) water eliminated only 10 percent or less. For fabrics that can't tolerate hot water, you'll need three rinses to effectively remove the dust mites. And since strong scents can aggravate allergies, use a fragrance-free detergent. Pop non machine-washables-like a stuffed animal-into a Ziploc bag and leave in the freezer overnight. The lack of humidity will kill any mites.
   
4. Travel wise. Remember: Your destination's allergy climate may be different than the one where you live. When you travel by car, bus or train, you may find dust mites, mold spores and pollen bothersome. Turn on the air conditioner or heater before getting in your car and travel with the windows closed to avoid allergens from outside. Travel early in the morning or late in the evening when the air quality is better. Remember, too, that air quality and dryness on planes can affect you if you have allergies.