MEMBER QUESTION:
Are air purifiers worth the money? Do they do what they say they will as far as removing mold spores and allergens out of the air?

SMART:
Yes. Many people who have allergies feel better when they run air filters. But you need to be careful with the air filter that you purchase. Consumer reports published a very good article last summer that tested the various air filter types, and found that the HEPA air filters work best, whereas the ion-based filters have been well advertised and have become very popular, but they don't work as well as a freestanding unit for a bedroom, for instance.

The other thing to know regarding air filters is that you have to be careful to match the air filter size to the room size. Usually the packaging will say the proper room size for the filter.

A third point is in order for the filter to work properly for the room the space needs to be kept closed. For a freestanding air filter for the bedroom you need to keep the bedroom doors and windows closed at all times and run the filter 24 hours per day. This will force you to run the air conditioning for the home, and most people notice they feel better with the air conditioning running anyway.


MEMBER QUESTION:
Is CO2 concentration a good indicator of room air quality? Should you always maintain humidity below 50%?

SMART:
I don't know how useful following CO2 levels is for measuring the home air quality; it's probably not very useful. But, yes, you are right, it is important for mold management, and also for dust mite management, to keep the home as dry as is reasonable. Most people feel too dry when the level drops below 30%. So for most people, you want the level between 30% and 50%.

MEMBER QUESTION:
After allergy testing I learned I am allergic to mold, dust mites, pollen, and certain trees. The asthma is only four months old and I have tried everything to relieve my symptoms. I just purchased dust mite-proof bedding -- cases, encasings, pillows, etc. How soon would one notice a change if mites are a big asthma/allergy trigger?

SMART:
Your particular situation is that you have multiple allergies, so making one single change for one of the allergies that you have may not lead to the huge change in symptoms that you seek. Most people, though, notice that they feel better with the dust mite covers fairly quickly; for instance, in a week or so.

Now, most people find that just the home measures, such as the dust mite covers and air filters and mold clean up, help them to feel better but are not adequate to fully manage their symptoms. That's the reason most people with allergies need medications, also.

MEMBER QUESTION:
Can allergies cause asthma?

SMART:
Yes. There are numerous things that can cause asthma, but the most common trigger is allergies. This is particularly true for children, for whom 85% with asthma do have allergies also.

MEMBER QUESTION:
I was tested for allergies and one of the allergens that I tested positive for was roaches! I've never heard of such a thing. Is this a common thing? How many roaches do you have to have to react to them?

SMART:
Yes. Roach allergy is very common. There was a paper published within the last year or so that showed that roaches cause allergies even for people in relatively affluent areas. Roaches aren't just an inner-city problem. You don't have to have a very large roach population to cause problems. So it's critical to act quickly when you find roaches.

What I usually suggest for patients with allergies is that when roaches are found you have them removed from the home as quickly as possible. The second point, though, is that the roaches themselves don't cause allergies, but it's the feces that they leave behind. So don't just have the roaches removed, but carefully clean up the area where they've been found.

Patients that I see who have roach allergy are usually surprised that they have the allergy, and they tell me they've never had a roach problem, which is very likely true. But there are lots of places to have roach contact that they don't think of like vacations, restaurants, schools, and even in formerly warehoused items. For instance, a couch that has been warehoused may have had some roach contact. So when the couch is brought into your home that may be the source of the roach allergy.

MEMBER QUESTION:
When one has a mold allergy should I assume this is all molds, including foods containing mold, such as wine, cheese, mushrooms, yogurt, etc.?

SMART:
No. The molds that cause allergies are the environmental molds, such as the molds that cause mildew or are growing on rotting leaves or other vegetation. Foods that are made with molds, such as cheese, won't cause mold allergy problems. Furthermore, foods that have some mold growth, such as bread that's become moldy, may or may not cause mold allergy problems.

The other question that people ask me regarding mold allergies is whether medications such as penicillin, which is made from mold products, may cause mold allergy problems, and the answer is no. So penicillin allergy is completely separate from mold allergy.

MODERATOR:
Dr. Smart, before we wrap things up, do you have any final words for us?

SMART:
As a closing comment I'd like to point out that you don't need to suffer with your allergy symptoms. Many people think that symptoms like sneezing or runny nose or coughing or wheezing are just normal for them and they keep suffering with these symptoms. These people should seek help. The vast majority of people who are suffering from asthma symptoms and from allergy symptoms can be helped to feel better. So you will sleep better, you will function better when working or when you're driving, and your overall health will be better.

MODERATOR:
Our thanks to Brian Smart, MD, for sharing his expertise with us. For more information, please be sure to visit our message boards to talk with others and ask questions of our experts.

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