Preventing Allergies


Air Filters

"What kind of air filter should I buy for my allergy?" I hear that question on a daily basis. In general, the answer is "it depends on what you're allergic to." If you are allergic to cat dander and grass pollen, and you have a cat in your home, I recommend investing in some sort of advanced filter. That's because these allergens are small; thus they are lighter than air and stay airborne indefinitely. That means they can actually be filtered out of the air. Now, let's compare that to dust mite allergy. Dust mite allergen is relatively large, staying airborne for about 15 to 20 minutes after being disturbed (such as making the bed). There's no way a filter can catch much dust mite allergen once it has settled back onto the bed or into the carpet.

Electrostatic filters are an interesting idea. You get a permanent metal filter that takes the place of your disposable fiberglass filter. The metal electrostatic filter is better at trapping allergens than the less expensive fiberglass model. However, consider these tips before you decide to go with electrostatic. First, you should run your air conditioning system using "ON" rather than "AUTOMATIC". You just paid for a good filter, and you want it filtering 24/7, right? Not just when your thermostat tells the compressor to blow cold air in the summer or tells the furnace to blow warm air in the winter. Second, be sure to clean the filter regularly with a strong flow of water. Most recommendations say to wash off the electrostatic filter once or twice a month, but it depends somewhat on how dusty your home is. If you don't keep an electrostatic filter clean, it will become less effective. It will also increase the drag on your entire HVAC system, making the system work harder. The company that services the air conditioners in my home doesn't like electrostatic filters at all, saying they reduce the life of the entire system. That company, AireServ, recommends that allergy patients consider an in-system High Efficiency Particulate Air (HEPA) filter. They sell the Lennox Healthy Climate, which is excellent, but expensive.

If you do get a filter, should you get a free-standing HEPA filter, a Sharper Image Ionic Breeze, or electro-static filters that replace your furnace filters in your home's air conditioning system? This depends somewhat on budget and noise tolerance. The HEPA filters have fans that make some noise. If you buy one, I recommend you get a Honeywell. After all, it's "the brand that doctors recommend most." Gag!! Actually, since it's a big seller, you'll be able to find the filters for it at any hardware store 15 years from now. Who is going to sell you the replacement filter for that Whirlpool or Vornado HEPA you bought 4 years ago? I don't know. I have a Honeywell in my bedroom, and we keep it on low speed when we're in there, and on high speed when we leave for the day. You have to change the pre-filter every 2 or 3 months. It's very easy to change, but take the unit outside before you disassemble it so the dust doesn't get messy. Changing the main filter is almost as easy, and only has to be done every couple of years.

The Sharper Image Ionic Breeze, with its huge advertising budget, has made quite an impact on the public, as well as the allergy community. With the professional marketing behind it, it is now thought by consumers to be the "best" filter out there. At least that's what it implies in its commercials. And besides, the Asthma and Allergy Foundation of America has given the Ionic Breeze its Seal of Truth. But what does that really mean?

AAFA does not endorse, recommend or advocate the purchase of any specific products, but AAFA will grant a "Seal of Truth" to products that meet scientific criteria determined by an independent panel of scientists including MDs, PhDs, MPHs and other medical, scientific and research experts. The AAFA Seal has been awarded to a variety of consumer products in many categories including vacuum cleaners, air filters, cleaning products and more.

To translate that last bit to English, if you have a product that works, and you pay AAFA $5000.00, they will allow you to use their Seal of Truth. Also, the seal states that the filter can "reduce airborne allergens and irritants..." As with most filters, it does NOT say it will reduce your symptoms, make you feel better, or allow you to use fewer medications. Currently, Sharper Image is giving dozens of my allergy colleagues large research grants to prove that their Ionic Breeze is an effective air cleaner AND can reduce symptoms scores. Sharper Image has certainly gotten its money's worth from that $5000.00 investment; however, I believe AAFA's sterling reputation has suffered. Both the American College of Allergy, Asthma and Immunology and the American Academy of Allergy, Asthma and Immunology have sent their members letters distancing themselves from that endorsement. That was a necessary step since both the College and the Academy have provided financial support to AAFA for many years. Stay tuned – this is exciting!

FULL DISCLOSURE – I own an Ionic Breeze GP model. We keep it in the room where our dogs, Spike and Rosie-Toes, sleep. A couple of my patients got one and raved about it, so I decided to give it a try. It does gather dust – we can see the dust every time we remove the filter to clean it. But, as Consumer Reports points out, my coffee table also gathers dust out of the air. That doesn't make it an air cleaner.

Lastly, the Ionic Breeze is NOT silent, as Sharper Image claims. Several of my patients agree with me that it hisses and pops whenever a tiny speck of dust hits the grid.

So what's the bottom line? If you're interested, get one if you can afford it and try it for 60 days. But keep all the packing materials, the box, and your receipt. If your symptoms aren't better after 59 days, pack everything up (including the receipt) in the box, take it back to The Sharper Image, and get your money back.

"No matter what filter you buy, you have to remember that a filter is just one step in a long process of allergen avoidance. If recommended by your doctor, you should also cover your mattress and pillow with impermeable covers; you should wash the sheets in hot water, remove the carpet from your bedroom, and keep the humidity in your home low enough to discourage growth of dust mites and mold."

Note: Information contained in this article should not be considered a substitute for consultation with a board-certified allergist to address individual medical needs.


Caveat Emptor

The Carpet and Rug Institute (CRI) used to advertise to doctors in physician journals claiming that carpeted rooms are actually better for the allergic patient than hard floors. I thought they would extend these ads to the public, but that has not happened yet. Dozens of scientific studies have been published in peer-reviewed, prestigious medical journals on the value of avoiding what you're allergic to. Almost all of them recommend removing carpeted surfaces and putting down tile, wood or linoleum instead. The references provided by the CRI that support carpeting being less allergenic than hard floors come down to one medical abstract; it was not accepted for publication in any peer-reviewed journal.

Their argument goes like this: when you walk on hard floors, you kick up pollen, dust mites particles, etc, that get into your "breathing zone". On the other hand, according to CRI, carpet traps these particles, thus protecting you from breathing them in.


By cleaning hard surfaces, you remove the allergens entirely. Carpeting, which provides dust mites with a nice, warm, moist environment to live, can never be totally cleaned of allergenic particles. Not even close. So keep your carpeting if you can control your allergy symptoms in spite of it, but don't install it because you think it will help with your allergies.

So, while the Carpet and Rug Institute puts its opinion all over the internet (including Wikipedia, unfortunately, claiming that carpet helps allergies and asthma, almost all researchers disagree:

Here are some examples: from BBC News and the American Academy of Allergy, Asthma & Immunology.

Note: Information contained in this article should not be considered a substitute for consultation with a board-certified allergist to address individual medical needs.


Humidify? Dehumidify?

Sometimes you read that you need a humidifier for your health, then you turn around and read that you need a dehumidifier to prevent the growth of mold, mildew and dust mites. This can be confusing. Before you buy either, find out if there is a problem. You can accurately measure humidity (water content of the air) with a digital humidity gauge. They are widely available and cost ~$20. Many also display the high and low humidity for the past 24 hours. The goal is to keep the humidity between 35 and 50%. Consider a dehumidier if the humidity is above 50%. Dust mites can't drink water; they have to absorb it from the air. Dust mites and mold grow better in higher humidity. High humidity also makes the air feel damp, which can worsen asthma and allergies. Consider a humidifier if the humidity is below 35%. Low humidity, more common in winter months, can cause dry, itchy skin, nosebleeds, sinus headaches and, like high humidity, flare asthma and allergies.

If you get a humidifier, rule #1 is Keep It Clean. They cause more problems than they solve if you start spewing bacteria and mold up into the air. Warm mist humidifiers are easier to keep clean than cool mist humidifiers, but the warm air may burn a child, so be careful. We tell patients that when they are infected, temporary use of a humidifier can reduce coughing and congestion and loosen the mucus. From April to October, your air conditioner probably takes adequate humidity out of the air, so you may only need to use a dehumidifier during Houston's winters.

Note: Information contained in this article should not be considered a substitute for consultation with a board-certified allergist to address individual medical needs.



The People for the Ethical Treatment of Dust Mites (P.E.T.D.M.) request a boycott of The Allergy Clinicbecause they continually advise their allergic patients to murder innocent dust mites. People allergic to dust mites have been advised to place barriers over their pillow cases and mattresses to reduce exposure to them.

Well, guess what? That deprives them of their food, starving them to death. Even worse, these allergy doctors counsel patients to wash their bed sheets and blankets in hot water. Wet heat KILLS dust mites. Dust mites have never intentionally caused any problems for humans. Trapping them in high filtration vacuum cleaner bags is absolutely UNETHICAL! How can they enjoy life inside a vacuum cleaner bag? Wouldn't it be more humane if the allergist advised patients to relocate dust mites to a special shelter where they could live in peace, without fear of deadly human hunters? Maybe even a reservation on a large farm put aside just for them. You could leave all your old carpets there so the dust mites would sleep comfortably, and have trucks bring in human skin cells for them to feast upon.

Allergists at The Allergy Clinic have advised patients allergic to dust mites to keep household humidity between 35% and 50% to inhibit their growth. (You don't want it much lower than 35% or you may get dry skin or even a bloody nose). That dry air causes dust mites to shrivel up and prevents them from making baby mites! Masks don't kill dust mites and wearing one while vacuuming keeps the allergen out of your nose while the vacuum cleaner is stirring dust up. Yes, we know that you have a super-duper Dyson, or Kirby, or Rainbow vacuum. Keep in mind, though, that the expensive vacuum cleaner with the perfect exhaust system may keep allergens in the bag instead of just recirculating them into the air like old vacuums; but, the brush at the vacuum's entrance stirs up more dust than it sucks in and propels allergens into the air – right into the operator's nose!

So, yes, we agree, wear a mask. But other measures that kill dust mites? Is that really how you want to treat these beautiful creatures? Well, maybe not beautiful; but, please feel obligated to rescue these creatures from being slaughtered just so the allergic can breathe easier.

Finally, one last thing...JUST KIDDING!!

Note: Information contained in this article should not be considered a substitute for consultation with a board-certified allergist to address individual medical needs.


Salt Water Rinse

I'm not sure if rinsing your nose with salt water is avoidance or if it's medication, but, either way, it's one of the most under-utilized treatments in chronic sinusitis and chronic rhinitis.

To get started, try dissolving a level teaspoon of salt and a pinch of baking soda in 8 ounces of distilled water, then rinsing the inside of your nose with this mixture. An infant's bulb syringe is an easy device to rinse with, but remember: with an infant, the purpose is to pull mucus out of the nose; with this adult salt water rinse technique, the purpose is to spray saline into your nose in order to irrigate mucus out.

You can also buy pre-packaged salt envelopes including an 8 ounce rinse bottle at Walgreen's under the name "Sinus Rinse", or get the easiest to use premixed form called "Simply Saline" at any pharmacy. Either way, you receive many benefits. Obviously, you moisten your nasal membranes and rinse away thickened secretions, which may cause obstruction. You also rinse out pollen or other allergens which you may have inhaled, lessening the chance of their promoting further allergic reactions.

Interestingly, though, you also rinse away some of the major basic protein (MBP). OK, what is MBP? It's one of the proteins released by the allergic white blood cells that helps protect you from becoming infected by germs. But when not busy fighting germs, too much MBP can also damage the protective lining of the nose and the lungs.

If you have chronic allergy or sinus symptoms, rinsing your nose with salt water will reduce the amount of MBP in your nose. Studies have shown that this simple, low-tech procedure, if done regularly, will reduce the symptoms and decrease the frequency of sinus infections.

Note: Information contained in this article should not be considered a substitute for consultation with a board-certified allergist to address individual medical needs.


Starve a Cold (of Antibiotics)

As we head into cold and flu season, many of us will catch a viral infection that will give us symptoms of a common cold: runny and/or stuffy nose, sore throat, cough, headache, and yellow mucus. So if we're infected, we should take an antibiotic, right? Wrong! Antibiotics don't work on viruses, and viruses cause colds. A review of sinus infections from the New England Journal of Medicine recommends against using antibiotics until the mucus has been yellow or green for at least 7 or 10 days (N Engl J Med 2004;351:902-910).

Many of the patients we treat for allergy to multiple antibiotics develop those allergies when their antibiotic is changed over and over again. It gets changed because they take the first antibiotic when the cold first appears. "Amazingly", the antibiotic does nothing to treat the virus, which continues to run it course. The patient, not feeling any better, asks for another antibiotic. And sometimes another. While the last antibiotic gets credit for curing the infection, the patient may become more likely to develop drug allergies.

For years, the line about chicken soup was, "Will it help?" "Well, it couldn't hurt". Scientific evidence now suggests why chicken soup helps. It contains the amino acid, cysteine, which has been shown to thin out thick mucus secretions and help relieve congestion. A similar mechanism of action helps Mucinex, available over the counter without a prescription, treat colds and sinus infections; basically increasing the water content of mucus to thin it out, so you can get rid of it.

What about "feed a cold, starve a fever". It's actually not a bad idea. A fever without cold symptoms may be the flu (influenza), another viral infection often manifest by nausea and vomiting. Starving the fever by temporarily withholding solid food is reasonable if one is vomiting. But make sure you're drinking plenty of Gatorade or Pedialyte so you don't get dehydrated.

What else works when you have a cold? Rinsing your nose out with a salt water solution a couple times a day makes many people feel much better. Go to NeilMed® for details; it's available at Walgreen's and CVS.

Just skip the antibiotics until the mucus has been yellow or green for at least a week.

Note: Information contained in this article should not be considered a substitute for consultation with a board-certified allergist to address individual medical needs.


Throw Your Mattress Away?

"Is your mattress full of dust mites? Then throw it away and come buy a new one from me!" That is not good advice. Buying a new mattress would solve the problem for about 6 months, until new dust mites had made a home for themselves in your new mattress. The dust mites come because you grow new skin; they feed on the old skin that you shed. The salesman would be happy selling you a new mattress every 6 months, but Consumer Reports says that you need to replace your mattress when it is no longer providing you comfort, not when it gathers dust mites.

To keep dust mites from bothering you while you sleep in your bed, here's what you need to know:

  1. Encase the mattress and pillow with a special cover that zips up and keeps the dust mites and their allergen away from you. You then put your sheets and pillow case on top of the covered mattress and pillow. But don't stop there. That is a good start, but effective treatment means also:
  2. Controlling humidity. The growth factors for dust mites are heat, and humidity. Dust mites cannot drink water; rather, they absorb moisture from the air. Relative humidity below 50% helps minimize growth of dust mites.
  3. Wash your sheets in HOT water. Wet heat kills dust mites. Once every week should do it.
  4. If possible, replace any bedroom carpeting with a hard, washable surface, such as tile, wood, or Pergo. Carpeting provides an ideal home for dust mites.
  5. Vacuuming carpet only throws the dust mite allergen up into the air for 30 minutes. Mites cling tightly to carpet fibers, and no vacuum has ever been shown to reduce dust mite levels enough to actually make a patient's symptoms better. Of course, the Carpet and Rug Institute disagrees on this point, but it seems as though they employ the same Junk Science experts who used to work for The Tobacco Institute. What the Practice Parameters actually say is, "Carpeting is best removed from the bedroom and replaced with smooth finish wood, tile, or vinyl flooring."



Note: Information contained in this article should not be considered a substitute for consultation with a board-certified allergist to address individual medical needs.


Tips on Dust Mites

Wet heat kills dust mites. That's why allergists tell their mite-allergic patients to wash their sheets and blankets in hot water. Here's another tip if you're in the market for a new washing machine: many new machines come with a "sanitary" cycle. This cycle lets the machine fill up with hot water, but then it heats the water up to 140 degrees Farenheit before starting the wash cycle.

That should be more effective in removing live mites from bedding. Other tips, such as encasing the pillow and mattress in dust-mite impermeable covers require purchasing special covers. They are sold at various stores, from Wal-Mart to Bed Bath & Beyond to internet sites, like Mission Allergy . Basically, you get what you pay for. But, even if money is no object, top notch mattress and pillow covers have failed to demonstrate a statistically significant difference in patients' symptoms. In 2003, two disappointing studies were published in the New England Journal of Medicine concluding that the use of allergen-impermeable bed covers as a single intervention for the avoidance of mite allergen had no clinical benefit for either allergic rhinitis or asthma.

I drew a different conclusion: If you're not going to replace the garbage dump (i.e., wall to wall carpeting) with a hard, washable surface, then don't bother with environment control for dust mite allergy. The studies that showed that environment control was effective had patients remove the carpeting. Time after time, including the 2003 articles, studies that failed to demonstrate clinical benefit did not insist upon patients removing their carpeting. What was particularly disturbing to me was that the New England Journal of Medicine's editor wrote, "The use of mattress and pillow covers that are impervious to house-dust mites need not be included in allergen-control measures." The editor's summary, like the article's abstract, is often the only bit of the journal that gets read by busy practitioners. It would be more appropriate to have said, "The use of mattress and pillow covers that are impervious to house-dust mites is ineffective unless combined with more intensive allergen avoidance techniques; specifically removal of bedroom carpeting."

Dr. Platts-Mills, a pioneer in dust mite research from the University of Virginia, said in an editorial:

As Woodcock and his colleagues take great care to point out, their study does not show or imply that allergen avoidance should not be recommended for patients with asthma who are allergic to dust mites. What their study shows very clearly is that distributing or recommending allergen-proof covers in a family-practice setting is unlikely to be effective as a single measure in the absence of a comprehensive avoidance strategy. The obvious implication of these studies is that mattress covers as a routine part of the treatment of asthma are not worth the price. However, according to other studies, the correct conclusion is that treatment by means of allergen avoidance requires the definition of what patients are allergic to, additional measures beyond the use of mattress covers, and education.

The following information is courtesy of Mission Allergy:

Dust mites are microscopic creatures that live in pillows, mattresses, blankets, carpets, and other soft materials. They are often thought of as insects, but are actually tiny arachnids, relatives of spiders and ticks. They do not live on people, but live near them. Their food is the dead skin scales that we all shed every day.

Dust mites avoid the light, and require at least 50% relative humidity to survive. They are therefore plentiful in soft materials, such as pillows, mattresses, and blankets, where they can burrow into the fabric to get away from the light. Beds provide the warmth, darkness, high humidity, and shed skin scales that mites crave, and they are the source of the biggest mite exposure for most of us. A mattress may contain over a million dust mites. A female mite lays about 60 eggs in her lifetime. Each mite lives for about 80 days, during which time it produces one thousand allergy-causing waste particles.

Live mites themselves are not inhaled. Rather, it is the waste particles that they have produced, and the body fragments of dead dust mites, that become airborne, are inhaled and cause allergy symptoms. This is because mites do not live in the air, but are burrowed in soft materials. Mite waste particles become briefly airborne when one walks on a carpet, sits on an upholstered chair, places one's face on a pillow, makes a bed, or otherwise disturbs the soft materials where the dust mites are living.

If you shop at Mission Allergy, here's how to save a little money: Mention Code: "DM5" before ordering. You'll get a 15% discount on Premium Microfiber encasings, or a 10% discount on Barrier Fabric II.

The Allergy & Asthma Foundation of America (AAFA)has certified the CleanRest brand of pillow and mattress encasings to be "Asthma Friendly". This brand is sold at Bed Bath & Beyond. If you go, be sure to bring your 20% off coupon that they send in the mail every few weeks. If your coupon is expired, bring it anyway---they always honor them.

Note: Information contained in this article should not be considered a substitute for consultation with a board-certified allergist to address individual medical needs.

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