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Subject: alt.support.asthma FAQ:  Asthma -- General Information
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Summary: This posting contains a list of frequently asked         questions and answers about asthma, including its         symptoms, causes, and forms of treatment.  It should         be of interest to anyone who has asthma or knows         someone who does.
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Last-modified: 17 September 2000
Original-author: Patricia Wrean <[email protected]>
Version: 5.3

      alt.support.asthma FAQ:  Asthma -- General Information
      ======================================================


Introduction:
------------

Welcome to alt.support.asthma!  This newsgroup provides a forum for
the discussion of asthma, its symptoms, causes, and forms of treatment.
Please note that postings to alt.support.asthma are intended to be
for discussion purposes only and are in no way to be construed as
medical advice.  Asthma is a serious medical condition requiring
direct supervision by a physician.

This FAQ attempts to answer the most frequently asked questions about
asthma on the newsgroup alt.support.asthma.  It was compiled by Patricia
Wrean <[email protected]> and is currently maintained by Marie
Goldenberg <[email protected]>.  The Asthma Medications FAQ is also posted
monthly as a companion to this one.  For information about allergies,
please see the alt.support.asthma FAQ:  Allergies -- General Information
(still under construction), and its companion posting, the Allergy
Medications FAQ.

Please be aware that the information in this FAQ is intended for
educational purposes only and should not be used as a substitute
for consulting with a doctor.  Most of the contributors are not
health care professionals; this FAQ is a collection of personal
experiences, suggestions, and practical information.  Please remember
when reading this that every asthmatic responds differently; what is
true for some asthmatics may or may not be true for you.  Although
every effort is made to keep this information accurate, this FAQ
should not be used as an authoritative reference.

Comments, additions, and corrections are requested; if you do not wish
your name to be included in the contributors list, please state that
explicitly when contributing.  I will accept additions upon my own
judgement -- I'll warn you right now that I'm a confirmed skeptic and am
not a great believer in alternative medicine.  All unattributed portions
are my own contributions or those of the original maintainer, Patricia
Wrean <[email protected]>.

+ = added since last version
& = updated/corrected since last version

======================================================================

Table of Contents:
-----------------

General Information:
    0.0  Changes since the last version
    1.0  What is asthma?
         1.0.1  What is chronic asthmatic bronchitis?
         1.0.2  What is status asthmaticus?
         1.0.3  What is anaphylactic shock?
         1.0.4  What is COPD?
         1.0.5  What is emphysema?
         1.0.6  What is bronchitis?
         1.0.7  What is pneumonia?
         1.0.8  What is cystic fibrosis?
    1.1  What is an asthma attack?
        1.1.1  What is wheezing?
        1.1.2  Do all asthmatics wheeze?
        1.1.3  What is "coughing asthma"?
        1.1.4  Is asthma hereditary?
    1.2  How is asthma diagnosed?
         1.2.1  What is a spirometer?
         1.2.2  What is a peak flow meter?
    1.3  How is asthma normally treated?
         1.3.1  How is an acute asthma attack treated?
    1.4  What are the most common triggers of asthma?
         1.4.1  What is intrinsic/extrinsic asthma?
         1.4.2  Can gastric reflux trigger asthma?
         1.4.3  What is occupational asthma?
    1.5  Asthma and Pregnancy

Medications:
    2.0  What are the major classes of asthma medications?
    2.1  What are the names of the various asthma medications?
         2.1.1  Are salbutamol and albuterol the same drug?
         2.1.2  Can albuterol be taken while taking salmeterol?
    2.2  Are some asthma drugs banned in athletic competitions?
    2.3  What kinds of inhalers are there?
         2.3.1  Do inhaler propellants bother some asthmatics?
         2.3.2  What is a spacer?  What is a holding chamber?
         2.3.3  What is "thrush mouth" and how can I avoid it?
         2.3.4  Is Fisons still making the Intal Spinhaler?
         2.3.5  What's the difference between Spinhalers and Rotahalers?
         2.3.6  Why are so many asthma drugs taken via inhaler?
         2.3.7  How can I tell when my MDI is empty?
         2.3.8  Are my aerosol inhalers going to disappear?
    2.4  What kinds of tablets are there?
         2.4.1  Why do I need a blood test when taking theophylline?
         2.4.2  Why are combination pills not commonly prescribed?
    2.5  What is a nebulizer?
    2.6  What medications should asthmatics be careful about taking?
         2.6.1  What about corticosteroids and chicken pox?

Miscellaneous:
    3.0  What resources are there for asthmatics?
    3.1  Where can I get the latest copy of the FAQs?
    3.2  What is an FAQ, anyway?  What is a Usenet newsgroup?
+    3.3  How about some other WWW links?

List of Contributors
References
Disclaimer

======================================================================

0.0  Changes since the last version
-----------------------------------
    September 17, 2000
    ------------------
    Asthma Gen: Added 3.3 WWW links section
    Asthma Gen: Added reference to Living Well With Asthma book
    Asthma Gen: Added reference to The Doser (inhaler counter) in section 2.3.7
    Asthma Med: Added reference to Advair (salmeterol / fluticasone)
    Asthma Med: Added reference to Bambec (bambuterol)
    Asthma Med: Added reference to Combivent (ipratropium / salbutamol)
    Asthma Med: Noted that Bronkaid and Isuprel appear to have been
                discontinued in Canada
    Asthma Med: Added reference to Xopenex (levalbuterol)
    Asthma Med: Added reference to Oxeze (formoterol) turbuhaler
    Asthma Med: Added reference to Pulmicort neb soln available in US

    September 17, 1998
    ------------------
    Asthma Med: Added note that Foradil (formoterol) now available in Canada

    February 17, 1998
    -----------------
    Asthma Med: Added Serevent Diskus, Flovent Rotahaler, Pulmicort,
         Airomir, Tilade nebulizer solution, and Singulair
         (newly approved medications)
    Asthma Med: Added note that Medihaler-Epi has been discontinued
    Allergy Med: Added note that Seldane has been discontinued
    Allergy Med: Added Nasonex (newly approved medication)
    Asthma General: Added section 1.4.3, Occupational asthma

    December 6, 1997
    ----------------
    Asthma General: Split web version of FAQ document into multiple-page
               format.


    August 17, 1997
    ---------------
    Asthma General: Added section 1.5, "Pregnancy and Asthma"

    Asthma General: Added reference to new version of NHLBI report

    Asthma General: Added reference to Adams book

    Asthma General: Correct reference to Gershwin to reflect 2nd edition


    June 17, 1997
    -------------
    Asthma General: Correct publication information on "Children With
    Asthma" by Dr. Plaut

    Asthma General: Added links to archived version of Allergy
    Medication FAQ

    May 17, 1997
    ------------
    Asthma Med: Added note that Nasalcrom now Over-The-Counter (OTC) in US.

    Asthma Med: Added Zyflo to Leukotriene Receptor Inhibitor section

    Asthma Med: Added Proventil HFA MDI

    Asthma General: Added discussion of phaseout of CFC
    (chlorofluorocarbon) MDIs

    Asthma General: removed comment that "both spinhaler and rotahaler are
    available in the US" (the spinhaler is not available in the US)


1.0  What is asthma?
--------------------

    Asthma is best described by its technical name:  Reversible
    Obstructive Airway Disease (ROAD).  In other words, asthma
    is a condition in which the airways of the lungs become
    either narrowed or completely blocked, impeding normal
    breathing.  However, in asthma, this obstruction of the lungs
    is reversible, either spontaneously or with medication.

    Quickly reviewing the structure of the lung:  air reaches the
    lung by passing through the windpipe (trachea), which divides
    into two large tubes (bronchi), one for each lung.  Each
    bronchi further divides into many little tubes (bronchioles),
    which eventually lead to tiny air sacs (alveoli), in which
    oxygen from the air is transferred to the bloodstream, and
    carbon dioxide from the bloodstream is transferred to the air.
    Asthma involves only the airways (bronchi and bronchioles),
    and not the air sacs.  The airways are cleaned by trapping
    stray particles in a thin layer of mucus which covers the surface
    of the airways.  This mucus is produced by glands inside the
    lung, and is constantly being renewed.  The mucus is then
    either coughed up or swept up to the windpipe (trachea) by
    cilia, tiny hairs on the lining of the airways.  Once the
    mucus reaches the throat, it can again be coughed up or,
    alternatively, swallowed.

    Although everyone's airways have the potential for constricting
    in response to allergens or irritants, the asthmatic's airways
    are oversensitive, or hyperreactive.  In response to stimuli,
    the airways may become obstructed by one of the following:
        - constriction of the muscles surrounding the airway;
        - inflammation and swelling of the airway; or
        - increased mucus production which clogs the airway.
    Once the airways have become obstructed, it takes more effort
    to force air through them, so that breathing becomes laboured.
    This forcing of air through constricted airways can make a
    whistling or rattling sound, called wheezing.  Irritation of
    the airways by excessive mucus may also provoke coughing.

    Because exhaling through the obstructed airways is difficult,
    too much stale air remains in the lungs after each breath.
    This decreases the amount of fresh air which can be taken in
    with each new breath, so not only is there less oxygen
    available for the whole body, but more importantly, the high
    concentration of carbon dioxide in the lungs causes the blood
    supply to become acidic.  This acidity in the blood may rise
    to toxic levels if the asthma remains untreated.


1.0.1  What is chronic asthmatic bronchitis?
--------------------------------------------

    Chronic asthmatic bronchitis is the condition in which the
    airways in the lungs are obstructed due to both persistent
    asthma and chronic bronchitis (see sections 1.0 and 1.0.6).
    People with this disease generally also have a persistent
    cough which brings up mucus.  Chronic asthmatic bronchitis
    which also involves emphysema is usually classified under
    the more general category of COPD.


1.0.2  What is status asthmaticus?
----------------------------------

    Status asthmaticus is defined as a severe asthma attack that
    fails to respond to routine treatment, such as inhaled
    bronchodilators, injected epinephrine (adrenalin), or
    intravenous theophylline.


1.0.3  What is anaphylactic shock?
----------------------------------

    Anaphylactic shock is defined as a severe and potentially
    life-threatening allergic reaction throughout the entire
    body.  It occurs when an allergen, instead of provoking a
    localized reaction, enters the bloodstream and circulates
    through the entire body, causing a systemic reaction.
    (There may also be an intrinsic trigger, as some cases of
    exercise-induced anaphylaxis have been reported.)

    The symptoms of anaphylactic shock begin with a rapid
    heartrate, flushing, swelling of the throat, nausea, coughing,
    and chest tightness.  Severe wheezing (asthma), cramping, and
    a rapid drop in blood pressure follow, which may lead to cardiac
    arrest.  Hives and vomiting are also common features.  The
    treatment for anaphylaxis is intravenous epinephrine (adrenalin),
    with antihistamines and steroids also being used in selected
    cases.  Aminophylline may also be given for pronounced asthmatic
    reactions that do not respond to epinephrine.


1.0.4  What is COPD?
--------------------

    COPD is chronic obstructive pulmonary disease, also known as
    either COAD, for chronic obstructive airway disease, or COLD,
    for chronic obstructive lung disease.  COPD is a disease in
    which the airways are obstructed due to a combination of
    asthma, emphysema, and chronic bronchitis.  The 1987 Merck
    Manual notes that "the term COPD was introduced because these
    conditions often coexist, and it may be difficult in an
    individual case to decide which is the major one producing
    the obstruction."

    [Maintainer's note:  the entries for COPD, emphysema, bronchitis,
    pneumonia, and cystic fibrosis have been included because of
    common confusion between the various diseases which can affect
    the lungs.]


1.0.5  What is emphysema?
-------------------------

    Emphysema is the disease in which the air sacs themselves, rather
    than the airways, are either damaged or destroyed.  This is an
    irreversible condition, leading to poor exchange of oxygen and
    carbon dioxide between the air in the lungs and the bloodstream.


1.0.6  What is bronchitis?
-------------------------

    Bronchitis is an inflammation of the bronchi, the large airways
    inside the lungs.  (Bronchiolitis is the inflammation of the
    bronchioles, the small airways.)  This inflammation often leads
    to increased mucus production in the airways.

    Bronchitis is generally caused either by a virus or by exposure
    to irritants such as dust, fumes, or cigarette smoke.  If caused
    by a virus, the bronchitis will likely be only temporary.  In
    the case of prolonged exposure to irritants, particularly
    cigarette smoking, if there is permanent damage to the bronchi,
    bronchitis may become chronic.


1.0.7  What is pneumonia?
-------------------------

    Pneumonia is an infection of the lung tissue.  In adults, it is
    generally caused by bacterial infections, though viruses, fungi,
    and protozoa may also be culprits.  The latter microorganisms
    have become very common as causes of pneumonia in immunosuppressed
    persons, such as those with HIV infection.  However, for those
    with chronic illnesses, especially cardiac or respiratory
    diseases, or those at increased risk for pneumonia, there is a
    pneumococcal pneumonia vaccination available as a preventive
    measure for the most common of these bacterial infections,
    streptococcus pneumoniae.  In children, pneumonia is most
    commonly caused by viruses.


1.0.8  What is cystic fibrosis?
-------------------------------

    Cystic fibrosis is a disease in which excessive amounts of
    unusually thick mucus are produced throughout the body.
    Because this mucus production also occurs in the lungs,
    people with cystic fibrosis are extraordinarily prone to
    bacterial infections which result in progressive lung damage.
    Cystic fibrosis can be diagnosed by a "sweat test" as people
    with cystic fibrosis have elevated chloride levels in their
    perspiration.  This condition often resembles asthma in
    children.


1.1  What is an asthma attack?
------------------------------

    An asthma attack, also known as an asthma episode or flare,
    is any shortness of breath which interrupts the asthmatic's
    well-being and requires either medication or some other form of
    intervention for the asthmatic to breathe normally again.


1.1.1  What is wheezing?
------------------------

    Wheezing is the whistling or rattling sound that occurs when
    air flows through obstructed airways.  At the start of an
    asthma attack, wheezing usually only occurs while exhaling, or
    breathing out, but as the attack progresses, wheezing may
    then be heard both while inhaling and exhaling.  If after
    the attack progresses further, the asthmatic then stops wheezing,
    this may indicate that many bronchioles (small airways) have
    become completely blocked, which is a very serious condition.


1.1.2  Do all asthmatics wheeze?
--------------------------------

    No, not all asthmatics wheeze.  Although wheezing is extremely
    common in asthmatics, in _All About Asthma_, Dr. Paul says,
    "It is important to note that not all asthmatic symptoms need be
    present for one to experience an asthma attack.  For instance,
    not all asthmatics wheeze.  And sometimes wheezing is so slight,
    it can only be heard with a stethoscope.  With some asthmatics,
    coughing is the only symptom present."  Similarly, in _Children
    with Asthma_, Dr. Plaut states that children with chronic coughs
    "may have asthma even though no wheezing is present."  He
    diagnoses such children with asthma if their peak flow improves
    when given an inhaled bronchodilator.


1.1.3  What is "coughing asthma"?
---------------------------------

    In _Children with Asthma_, Dr. Plaut defines "coughing asthma"
    as "a form of asthma in which coughing is the only symptom and
    there is no abnormality in any lung function test."  This
    condition is also known as "cough variant asthma."  Coughing
    asthma often improves when standard asthma medications are
    taken.


1.1.4  Is asthma hereditary?
----------------------------

    No, asthma itself is not hereditary, but there does seem to be
    a hereditary component to the tendency to develop asthma.  In
    _All About Asthma_, Dr. Paul states that if neither parent has
    asthma, the chances of each of their children having asthma are
    less than 10%.  When one parent has asthma, the chances rise to
    25%, and when both parents have asthma, the chances climb to 50%.
    (Actually, there is considerable disagreement among my sources
    as to the exact numbers, but all agree that the chances climb
    dramatically if one or both parents have asthma.)

    Similarly, if one or both parents have allergies, the chances
    of each of their children having allergies are 35% and 65%,
    respectively, compared to a less than 10% chance if neither
    parent has allergies.

    However, Dr. Paul cautions that "children don't inherit asthma
    itself, but the tendency to develop it."  Whether or not an
    individual develops asthma is also influenced by their exposure
    to various other factors such as infections, irritants, and
    allergens.


1.2  How is asthma diagnosed?
-----------------------------

    Asthma is diagnosed based on a physical examination, personal
    history, and lung function tests.  The physical examination looks
    for typical asthma symptoms such as wheezing or coughing, and the
    personal history provides additional clues such as allergies or a
    familial tendency towards asthma.  Although lung function tests
    have not always been used for diagnosis in the past, the NHLBI
    Guidelines for the Diagnosis and Management of Asthma state that
    "Pulmonary function studies are essential for diagnosing asthma
    and for assessing the severity of asthma in order to make
    appropriate therapeutic recommendations.  The use of objective
    measures of lung function is particularly important because
    subjective measures, such as patient symptom reports and
    physicians' physical examination findings, often do not correlate
    with the variability and severity of airflow obstruction."
    Lung function tests may be as simple as measuring peak flow with
    a peak flow meter, or using a simple spirometer, or may involve
    a battery of spirometry tests in a pulmonary function lab.


1.2.1  What is a spirometer?
----------------------------

    A spirometer is a machine for testing lung function that you
    breathe in and out of through a hose attached to a mouthpiece.
    You are usually given nose clips so that all the air you breathe
    goes through the machine.  One I've been tested on had a little
    expanding tank surrounded by water into which the air goes, and
    I could see the top rising and falling as I breathed out and in.
    It can measure a fair number of characteristics of your lungs,
    including FVC, FEV1, and PEPR.  FVC, or forced vital capacity,
    is the amount of air that you can exhale forcefully after taking
    a deep breath.  FEV1, or forced expiratory volume in one second,
    is the amount of air that you can be exhale in one second.
    Peak flow, or PEPR, is described in section 1.2.2.
    The sophisticated spirometers I've seen have a PC attached, and
    have neat little curves generated with each breath, which
    apparently have characteristic shapes for different respiratory
    diseases.

    There is a slightly less sophisticated machine that I've blown
    into, and I'm not sure if this is also classed as a spirometer or
    not, but you take a deep breath and blow into it, much like a
    peak flow meter, except that it draws a little graph of how much
    volume you've blown out, and I'd imagine that you can get the
    FVC and FEV1 off this graph.

    For more information, I recommend the book by Drs. Haas,
    _The Essential Asthma Book_, which goes into more detail about
    the various things you can find out from spirometry.


1.2.2  What is a peak flow meter?
---------------------------------

    A peak flow meter is a little plastic device which you blow hard
    into, after having taken a deep breath.  It records the rate at
    which you've blown into it in litres exhaled per minute (L/min)
    -- this is called the peak expiratory flow rate (PEF or PEFR).
    The meter is essentially a cylinder with a mouthpiece at one end,
    a place for the air to escape at the other end, and a calibrated
    meter along the side.  When you blow into it, a marker is pushed
    along the scale and comes to rest at a point which indicates your
    PEF.  Since you want to measure your maximum peak flow, it is
    important to take a deep breath and blow as hard and as fast as
    you can.  Many asthmatics find that their maximum peak flow provides
    a good objective measure of how their asthma is doing, so peak flow
    meters now are used extensively for self-monitoring of asthma, and
    also for monitoring the effectiveness of asthma medications.


1.3  How is asthma normally treated?
------------------------------------

    Treatment of mild asthma usually tries to relieve occasional
    symptoms as they occur by use of short-acting, inhaled
    bronchodilators.  Treatment of moderate or severe asthma,
    however, attempts to alleviate both the constriction and
    inflammation of the airways, through the use of both
    bronchodilators and anti-inflammatories.  Bronchodilators are
    drugs which open up or dilate the constricted airways, while
    drugs aimed at reducing inflammation of the airways are called
    anti-inflammatories.

    Taking anti-inflammatory drugs (usually inhaled corticosteroids)
    daily for moderate to severe asthma is a relatively new approach
    to treating asthma.  The idea behind it is that if the underlying
    inflammation of the airways is reduced, the bronchi may become
    less hyperreactive, making future attacks less likely.  Such
    anti-inflammatory therapy, however, must be taken regularly in
    order to be effective.

    For asthma which is strongly triggered by allergies, allergen
    avoidance can often greatly reduce the amount of medication
    needed to control the asthma.  Taking anti-allergic medications
    or taking shots for allergy desensitization are other
    alternatives.  For more information about allergen avoidance
    and allergies in general, please see the alt.support.asthma FAQ:
    Allergies -- General Information (still under construction).


1.3.1  How is an acute asthma attack treated?
---------------------------------------------

    An acute asthma attack is usually treated with bronchodilators
    to reduce the constriction of the airways.  Intravenous adrenalin
    and theophylline are often given in emergency rooms for this
    purpose, if short-acting bronchodilators given by nebulizer
    haven't sufficiently controlled the attack.

    Once the acute attack is over, anti-inflammatories may be used to
    reduce the inflammation of the airways.  Inhaled steroids are
    usually the first choice, but for a sufficiently severe attack,
    oral steroids such as prednisone may also be given.


1.4  What are the most common triggers of asthma?
--------------------------------------------

    The most common triggers of asthma are:
        - viral respiratory infections, such as influenza (the flu)
          or bronchitis;
        - bacterial infections, including sinus infections;
        - allergic rhinitis;
        - irritants, such as pollution, cigarette smoke, perfumes,
          dust, or chemicals;
        - sudden changes in either temperature or humidity, especially
          exposure to cold air;
        - allergens, for people with allergies;
        - emotional upsets, such as stress; and
        - exercise.


1.4.1  What is intrinsic/extrinsic asthma?
------------------------------------------

    Intrinsic and extrinsic asthma are outdated terms which have now
    been replaced by terms related to the asthma trigger, since the
    inflammatory response of the airways is the same independent of
    the cause of the asthma.  What was known as extrinsic asthma is
    now called allergic asthma, while asthma triggered by non-allergic
    factors, formerly called intrinsic asthma, is separated into such
    categories as exercise-induced asthma and occupational (chemical-
    induced) asthma.


1.4.2  Can gastric reflux trigger asthma?
----------------------------------------

    Yes, gastric reflux can act as an irritant which triggers
    asthma.  Reflux, properly known as gastroesophageal reflux,
    occurs when the liquids in the stomach pass up the esophagus,
    or feeding tube.  Because these liquids are usually highly
    acidic, they can irritate and inflame the esophagus, and
    also the airways of the lung, should any of this liquid be
    aspirated.  This irritation can trigger an asthma attack.

    Asthma flares caused by reflux are more common at night,
    for it is easier for material to pass up the esophagus when
    one is lying down.  Some simple treatments to prevent reflux
    include raising the head of the bed, not eating close to
    bedtime, or using either antacids or medications such as
    ranitidine (Zantac) which reduce the amount of acid produced
    by the stomach.

    Contributed by: Betty Bridges                      [email protected]

1.4.3  What is Occupational Asthma?
-----------------------------------
    Occupational Asthma is asthma that is caused by sensitization from
    exposures in the workplace.  Asthmatics whose asthma is exacerbated by
    exposures in the workplace would not be classified as having
    occupational asthma.

    There are over 200 substances that have been documented as causing
    occupational asthma, but there are probably more that have not been
    recognized. The substances that are known to cause occupational asthma
    can be divided into two main categories.

    High molecular weight proteins of animal or plant origins are common
    causes.  Things like animal dander, flour proteins, and animal scales
    are frequently causes of occupational asthma.  These same things are
    also common causes of non-occupational asthma.  These are usually
    IgE-mediated responses.

    Low molecular weight chemicals that have the ability to bind with
    proteins or act as haptans are causes of occupational asthma.  There
    may be other mechanisms involved besides the classic IgE-mediated
    responses as not all those that are sensitized have specific
    antibody production.  Reactions may have reflex, inflammatory,
    pharmacological, or immunologic pathways or a combination of several.

    Often occupational asthma is difficult to diagnosis.  There are may be
    immediate, late, or biphasic reactions.  In late reactions the symptoms
    may not occur until away from the work place.  Frequently the asthma
    worsens as the workweek progresses and improves over the weekend.

    Treatment for occupational asthma is basically the same as any other
    asthma with a few very important exceptions.  For those that have
    chemically induced asthma from sensitization to that chemical;
    avoidance of the trigger is essential. While steroids and other
    medications are helpful in treating the symptoms, they do not
    prevent the underlying sensitivity from increasing.

    Once sensitized to a substance, some react to minute amounts.  Levels
    below current TLV levels still trigger reactions. For a sensitized
    individual any exposure can cause symptoms.

    Continued exposure to the triggering chemical can cause permanent lung
    damage, chronic asthmatic conditions, and even death.  Medication
    should never be used to allow the worker to continue to work in an
    environment where there is exposure to the triggering substance.  Early
    recognition and removal from exposure is essential in preventing long
    term disability from asthma.

    Chemically induced asthma can occur both in the workplace and outside
    of the workplace.  There are many exposures outside of the workplace
    that there are exposures to chemicals that can induce asthma.  Most
    physicians are not familiar with this type of asthma. For anyone that
    has chemically induced asthma, avoidance of the trigger is essential.

1.5  Asthma and Pregnancy
-------------------------
    Many people have posted to ask about whether it is safe to become
    pregnant while suffering from asthma, and in particular whether it is
    safe to use their asthma medications while pregnant.

    The general consensus (from the doctors I have consulted) is that
    asthmatics can safely become pregnant without undue worry about whether
    the mother and the baby will be all right.  Most doctors talk about a
    "rule of 1/3" by which they mean that roughly 1/3 of all asthmatics get
    better while pregnant, 1/3 stay the same, and 1/3 find their asthma is
    aggravated (I improved with one pregnancy, and stayed the same with the
    next).

    In any event, the bottom line when pregnant is ensuring that the baby
    receives sufficient oxygen - and medications should be used as
    appropriate to control the asthma and protect mother and child.
    It is inadvisable to stop or reduce asthma medication solely because
    of the pregnancy without careful supervision, as this can lead to
    poorly controlled asthma, unnecessary ER visits, and poor outcome for
    the baby and/or mother.

    Most commonly-used asthma medications appear to be safe when used in
    pregnancy; notable exceptions include the combination pills (Marax,
    Tedral etc.) and those containing iodine (e.g. Theo-Organidin).
    Many people are concerned in particular with the use of inhaled,
    intranasal, and/or oral steroids but it has been my experience that
    most doctors are quite willing to use these as needed, especially the
    inhaled and intranasal steroids. It is my understanding that ephedrine
    (alone or in combination drugs), and phenobarbital (an ingredient in
    Tedral and other combination drugs) should be avoided.

    There are choices in most classes of drugs, e.g., the bronchodilators,
    and many doctors will elect to put their patients on those drugs with
    the longest history of use in pregnant women - the assumption is that
    the longer a drug has been in use, the likelier it is that any problems
    would have become evident.  For this reason, beclomethasone (Beclovent,
    Vanceril) is the preferred inhaled corticosteroid.  Cromolyn Sodium
    (Nasalcrom, Intal) also appears to be safe for use in pregnancy.

    In addition, if you need to use systemic steroids for a brief flareup,
    old concerns over fetal abnormalities (cleft palate etc.) appear to
    be less worrisome; I know of one case in which a woman used prednisone
    for something other than asthma for several months while pregnant and
    her baby had no problems.

    Antibiotics may be used if needed; there are some such as tetracycline
    which should be avoided but others (such as penicillin) appear to be
    safe.

    There is some anecdotal evidence from one contributer to the newsgroup
    that Serevent, the longer-acting B2-agonist, might be related to several
    cases of fetal abnormalities; I have not seen any official reports
    supporting or denying this but it may be worth discussing with your
    doctors if you use Serevent and are considering pregnancy.

    Note: the above is a compilation of my own experiences as a pregnant
    asthmatic, anecdotes from the newsgroup, and excerpts from The Asthma
    Sourcebook and the National Asthma Education and Prevention Program
    Expert Panel Report.  It should in no way substitute for consultation
    with qualified medical personnel.



======================================================================

2.0  What are the major classes of asthma medications?
------------------------------------------------------

    There are seven major classes of asthma medications:
        - steroidal anti-inflammatories,
        - non-steroidal anti-inflammatories,
        - beta-agonists,
        - xanthines,
        - anticholinergics,
        - leukotriene receptor antagonists, and
        - anti-allergics.

    The first two categories of drug treat the underlying
    inflammation of the lung.  All steroidal anti-inflammatories
    are glucocorticosteroids, which are entirely different from the
    anabolic steroids that have become notorious for their abuse
    by athletes.  There are many different corticosteroids available
    for the treatment of asthma, almost all available via inhaler
    to reduce the amount of side effects (see section 2.3.6).  The
    non-steroidal anti-inflammatories currently available are
    nedocromil sodium and cromolyn sodium, though cromolyn sodium
    is perhaps more properly known as a mast cell stabilizer, since
    it blocks both the release of histamine and inflammatory
    mediators, which means that although it blocks the inflammatory
    response, it cannot reverse inflammation once it has taken place.
    For this reason, I have classed it as an anti-allergic since it
    is mostly commonly taken for asthma that has a strong allergy
    component.

    The second two classes of asthma medications, beta-agonists and
    xanthines, are both bronchodilators, meaning that they relax the
    muscles lining the airways, allowing the airways to expand to
    their normal size.  Beta-agonists are chemically related to
    adrenalin, but are specifically tailored to be more effective
    on the muscles of the lung while having little effect on the
    muscles in the heart.  They are usually taken in inhaled form,
    and all but one (salmeterol) are short-acting.  Theophylline,
    the major xanthine, is chemically related to caffeine, since
    caffeine is also a xanthine derivative, and is present in tea.
    Theophylline is taken orally, often in a sustained-action form
    (see section 2.4).  Because its therapeutic range is close to
    its toxic range, asthmatics taking theophylline should have
    their blood levels monitored to ensure that their blood
    concentrations of theophylline lie within the therapeutic
    range (see section 2.4.1).  There are some asthmatics, however,
    who cannot tolerate even very low doses of theophylline.

    Anticholinergics, the fourth class of medication, work by
    blocking the contraction of the underlying smooth muscle of
    the bronchi.  Although used to treat asthma in Canada, the
    anticholinergic ipratropium bromide (Atrovent) has not approved
    by the US Food and Drug Administration for the treatment of
    asthma, but is used for the treatment of COPD.
    (It is interesting to note, however, that in the April 1982
    issue of The FDA Drug Bulletin, the FDA states that "the
    FD&C Act does not, however, limit the manner in which a
    physician may use an approved drug.  Once a product has been
    approved for marketing, a physician may prescribe it for uses
    or in treatment regimens or patient populations that are not
    included in a approved labeling."  The FD&C Act is the Food,
    Drug, and Cosmetic Act.)

    The newest class of asthma medications is leukotriene receptor
    antagonists.  My information as to how they work is sketchy,
    but as I understand it, the leukotriene receptor starts off the
    inflammator response of the immune system when it detects an
    allergen, so presumably an antagonist would block the receptor
    from responding to the presence of an allergen.  Zeneca
    Pharmaceuticals has just now announced that its new leukotriene
    receptor antagonist, zafirlukast (Accolate), has been approved
    by the FDA (the US Food and Drug Administration) and will be
    available in November of 1996.  Abbott Laboratories now produces
    a second drug in this class: zileuton (Zyflo).

    The last class, the anti-allergics, has been included because
    the two anti-allergic drugs, cromolyn sodium and ketotifen, are
    commonly taken for the prevention of allergic asthma.  Cromolyn
    sodium is a mast cell stabilizer -- it blocks the release of
    histamine from mast cells, which acts to prevent asthma flares
    since histamine is a very strong bronchoconstrictor.  However,
    it isn't considered an antihistamine because it cannot prevent
    the effects of histamine once the histamine has been released
    from the cell.  Similarly, it blocks the release of inflammatory
    mediators from the mast cell, and so prevents the inflammatory
    response, although it cannot reverse inflammation once the
    mediators have been released.  Ketotifen fumarate (Zaditen),
    a non-sedating antihistamine used mostly for the treatment of
    pediatric allergic asthma, is not currently available in the
    United States.


2.1  What are the names of the various asthma medications?
----------------------------------------------------------

    For a complete listing of asthma medications, please see the
    alt.support.asthma FAQ:  Asthma Medications.  Allergy medi-
    cations are listed in the alt.support.asthma FAQ: Allergy
    Medications.  They are posted monthly as companions to this
    general information FAQ.


2.1.1  Are salbutamol and albuterol the same drug?
--------------------------------------------------

    Ventolin is the brand name of salbutamol, which is the WHO
    (World Health Organization) recommended name for the medication.
    Unfortunately, in the US this same drug is called albuterol,
    leading to endless confusion.  In fact, it's one of the few
    drugs in which the brand name stays the same from country
    to country, while the chemical name changes!  Ventolin is made
    in the U.S. by Allen & Hanburys, and Proventil is the same drug
    manufactured by Schering.  You can also get this drug in
    a sustained-action tablet, called either Repetabs (by Schering,
    again) or Volmax (Muro).


2.1.2  Can albuterol be taken while taking salmeterol?
------------------------------------------------------

    Yes.  Quoting from the Product Information Sheet that comes
    with the Serevent (salmeterol) inhaler, manufactured by
    Allen & Hanburys:

    "Serevent Inhalation Aerosol should not be used more frequently
    than twice daily (morning and evening) at the recommend dose.
    When prescribing Serevent Inhalation Aerosol, patients must be
    provided with a short-acting, inhaled beta2-agonist
    (e.g., albuterol) for treatment of symptoms that occur despite
    regular twice-daily (morning and evening) use of Serevent."

    "When patients begin treatment with Serevent Inhalation Aerosol,
    those who have been taking short-acting, inhaled beta2-agonists
    on a regular daily basis should be advised to discontinue their
    regular daily-dosing regimen and should be clearly instructed to
    use short-acting, inhaled beta2-agonists only for symptomatic
    relief if they develop asthma symptoms while taking Serevent
    Inhalation Aerosol."

    "The safety of concomitant use of more than eight inhalations per
    day of short-acting beta2-agonists with Serevent Inhalation
    Aerosol has not been established."

    So the above quotes seem to imply that it is okay for asthmatics
    taking Serevent regularly to also use Ventolin (albuterol) as
    needed, provided one doesn't need it too often.


2.2  Are some asthma drugs banned in athletic competitions?
-----------------------------------------------------------

    The determination of whether a drug or substance is banned or
    allowed in amateur athletic competitions is not based on whether
    it is medically necessary.  Rather, such a determination is based
    on whether the substance in question can be performance-enhancing
    and offer an unfair competitive advantage.  There are several
    organizations that make this determination and an athlete on an
    asthmatic drug should check with his coaches, physician, and
    appropriate athletic authority.  Different athletic organizations
    may differ on what is banned or allowed.  For example, the
    United States Olympic Committee (USOC) follows International
    Olympic Committee guidelines for testing at Olympic events.  Many
    amateur athletic organizations (termed National Governing Bodies)
    adopt USOC guidelines for drug testing at their events.  In
    contrast, the NCAA has less stringent guidelines for certain
    substances used by asthmatics in during competitions.  Further
    complicating an athlete's understanding of the situation, some
    substances that are banned in tablet form are allowed in inhaled
    form.

    As an example, the USOC allows inhaled forms of the beta-2 agonist
    albuterol with written notification by a treating physician but
    bans tablet forms of albuterol.  Certain other beta-adrenergic
    agonists (e.g. ephedrine, bitolterol, metaproterenol) are banned
    by the USOC.  An athlete who participates in an amateur athletic
    event where drug testing may occur should check with his or her
    coaches and physicians regarding the allowed vs. banned status of
    any substance while competing.  The United States Olympic
    Committee Drug Hotline, (800) 233-0393, or NCAA, (800) 546-0441,
    may provide information to specific questions on drugs, and
    educational materials in this regard.  An asthmatic should also
    not assume that an over-the-counter (OTC) status of any drug
    implies its allowed status in athletic competitions; many OTC
    agents (e.g. combination decongestant-bronchodilators containing
    ephedrine) or herbal preparations bought in food stores
    (e.g. Ma Huang) contain stimulants useful for asthma but banned
    in certain athletic competition settings.

    Contributed by:  Lyn Frumkin, M.D., Ph.D. [email protected]


2.3  What kinds of inhalers are there?
--------------------------------------

    aerosol inhalers:
    ----------------

    MDI         - metered-dose inhaler, consisting of an aerosol unit
                  and plastic mouthpiece.  This is currently the most
                  common type of inhaler, and is widely available.

    autohaler   - MDI made by 3M which is activated by one's breath,
                  and doesn't need the breath-hand coordination that
                  a regular MDI does.  Available in U.S., UK, and NZ.

    integra     - MDI with compact spacer device.  Available in UK.

    respihaler  - aerosol inhaler for Decadron.  I have no idea how
                  this differs from the usual MDI.  Available in the
                  U.S.

    syncroner   - MDI with elongated mouthpiece, used as training device
                  to see if medication is being inhaled properly.
                  Available in Canada and UK.


    dry powder inhalers:
    -------------------

    accuhaler   - dry powder inhaler for use with Serevent.  It contains
                  a foil strip with 60 blisters, each containing one dose
                  of the drug.  Pressing the lever punctures the blister,
                  allowing the drug to be inhaled through the mouthpiece.
                  Available in the UK.

    diskhaler   - dry powder inhaler.  The drug is kept in a series of
                  little pouches on a disk; the diskhaler punctures
                  the pouch and drug is inhaled through the mouthpiece.
                  Currently available in Canada, South Africa, and UK,
                  not in U.S.

    insufflator - dry powder nasal inhaler used with Rynacrom
                  cartridges.  Each cartridge contains one dose;
                  the inhaler opens the cartridge, allowing the
                  powder to be blown into the nose by squeezing
                  the bulb.  Available in Canada.

    rotahaler   - dry powder inhaler used with Rotacaps capsules.
                  Each capsule contains one dose; the inhaler opens
                  the capsule such that the powder may be inhaled
                  through the mouthpiece.  Available in the U.S.,
                  Canada, and UK for Ventolin.  In Canada, Beclovent
                  Rotacaps are also available, as are Becotide
                  Rotacaps in the UK.

    spinhaler   - dry powder inhaler used with Intal capsules for
                  spinhaler.  Each capsule contains one dose; the
                  inhaler opens the capsule such that the powder
                  may be inhaled through the mouthpiece.  Available
                  in Canada, UK, and the Netherlands.  No longer
                  manufactured in the U.S.

    turbuhaler  - dry powder inhaler.  The drug is in form of a pellet;
                  when body of inhaler is rotated, prescribed amount of
                  drug is ground off this pellet.  The powder is then
                  inhaled through a fluted aperture on top.  Available
                  in Australia, Canada, Denmark, Switzerland, and
                  the UK (spelled 'turbohaler' in the UK).


2.3.1  Do inhaler propellants bother some asthmatics?
-----------------------------------------------------

    Some asthmatics find the dry powder inhalers more effective than
    their MDI (aerosol) counterparts.  It is suspected that the
    aerosol or propellant in the MDI may act as an irritant to some
    asthmatics, as in the following article:

    J.R.W. Wilkinson et al., Paradoxical bronchoconstriction in
    asthmatic patients after salmeterol by metered dose inhaler,
    British Medical Journal 305 (1992) 931.  The first sentence
    in the conclusion is:  "Bronchoconstriction after both
    salmeterol and placebo by metered dose inhaler but not after
    salmeterol by diskhaler suggests that the irritant is not
    the salmeterol itself."  . . . "The similarity in characteristics
    of bronchoconstriction after beclomethasone by metered dose
    inhalers implicates one or both chlorofluorocarbons . . . as
    the irritant.  That salbutamol caused no bronchoconstriction was
    attributed to its faster onset of action opposing any
    bronchoconstrictor effects of the propellants."

    ** However, according to the 1994 Physicians' Desk Reference,
       Intal Spinhaler capsules are "contraindicated in those
       patients who have shown hypersensitivity to . . . lactose."
       So asthmatics who are lactose-intolerant may not have this
       form of cromolyn sodium as an option.


2.3.2  What is a spacer?  What is a holding chamber?
----------------------------------------------------

    Metered dose inhalers (MDIs) for asthma medications typically
    consist of a metal aerosol canister (containing the medication and
    a propellant) in a plastic sleeve with a mouthpiece.  The patient
    inhales one or more metered doses of a medication through the
    mouthpiece.  Most people find it difficult (at least initially) to
    time the spraying of an MDI and the inhalation of the medicine:
    the patient must exhale fully and inhale and release the metered
    dose just at the beginning of the inhalation so as to draw the
    medication as fully and deeply into the lungs as possible.

    All too often the puffs are mis-timed and only make it part of the
    way into the airways, and some of the medication is invariably
    deposited into the mouth and on the back of the throat instead of
    into their lungs.  In addition to being less effective, this can
    lead to other side effects (e.g., for inhaled steroids, an
    increased potential for thrush, an oral fungal infection described
    in section 2.3.3).

    Several devices have become available that address these
    difficulties to varying degrees.  The devices are generally
    referred to as "spacers" since they place additional space between
    the patient and the MDI.  The medication is sprayed into the spacer
    instead of the mouth.  As the patient inhales, the column of
    medication passes through the mouth and throat relatively quickly,
    leaving little opportunity for the medication to be deposited in
    the mouth or throat.  This is a more efficient means of delivering
    the medication to the airways where it's most needed.

    The simplest kind of spacer is basically a tube.  The patient
    sprays the medication in one end of the tube and inhales it out
    the other end.  Azmacort has a simple spacer attached to it.  A
    cardboard tube from the core of a roll of bathroom tissue can be
    used as a spacer (as long as it's clean, lint-free and germ-free).
    While a simple spacer reduces the amount of medication that gets
    deposited in the mouth and throat, it still requires you to
    carefully time your inhalation with the discharge of the
    medication to minimize the amount of the medication that escapes
    from the spacer.

    A "holding chamber" is a more sophisticated device.  It is a sealed
    chamber (once the inhaler is inserted) that traps and holds the
    medication, allowing the patient to spray the medication into the
    chamber and take a few seconds to inhale the medication.  Since
    the medication is temporarily suspended in the holding chamber,
    the timing of the inhalation is not nearly as critical as with
    simple spacers or no spacer.  AeroChamber is a brand of holding
    chamber.  It's a plastic tube with a mouthpiece on one end and a
    place to insert the MDI on the other.  The mouthpiece has a
    one-way valve built in that temporarily contains the sprayed
    medication, and also allows the patient to exhale without
    displacing the medication in the chamber (as without a spacer, the
    patient should exhale as completely as possible before taking in
    any medication, so that the medication can be inhaled as deeply as
    possible).

    In addition to improving the timing of the inhalation, a holding
    chamber makes it possible to take in the medication more slowly
    than is possible without a spacer or with a simple spacer.  This
    is important for the symptomatic patient, since rapid inhalation
    of the medication is more likely to trigger coughing and cause the
    patient to lose the medication before it has had a chance to be
    absorbed.

    Some spacers are clear so that you can see the puff of medicine,
    and so that you can see when the medication is building up on the
    inside, indicating that the spacer needs cleaning.

    Spacers and holding chambers need periodic cleaning; clean
    carefully, following the manufacturer's instructions so as not to
    damage any delicate internal parts or allow molds or other
    contaminants to be introduced.

    There are special holding chambers for younger children.  There's
    a pediatric Aerochamber that has a mask built in; the child
    breathes normally for a few seconds with the mask held over
    his/her mouth and nose.  This is typically used when a nebulizer
    is not available or not required, and for medications that are not
    available in a nebulized form, such as Beclovent or Vanceril.

    There is also a device for children (and for people that have
    trouble holding their breath) called an InspirEase.  It's kind
    of like a plastic bellows or balloon with a plastic mouthpiece.
    The patient inflates it, the medicine is sprayed into it, and the
    patient inhales, holds his/her breath for the count of 5 (or
    whatever the doctor recommends), exhales into the device, and then
    repeats.  Some patients are instructed to breath slowly in and out
    several times instead of holding their breath.  The InspirEase
    really helpful for younger children who yet aware of the
    difference between breathing in and breathing out or don't yet
    know how to hold their breath or breathe evenly and slowly.  It
    gives them immediate physical feedback, and it also  has a whistle
    built in to tell them when they're breathing too fast (although
    they seem to like making it whistle, so it's positive
    reinforcement for something that they shouldn't be doing).  As the
    child grows, the Inspirease becomes less effective, since it has a
    limited capacity, although I've been told that it is available in
    different capacities.

    Knowing the difference between a simple spacer and a holding
    chamber can help you use each in its proper way.  If you use both a
    holding chamber *and* a simple spacer (e.g., a holding chamber for
    your Ventolin and the simple spacer attached to your Azmacort),
    you need to remember which you're using and adjust your style
    accordingly.

    Spacers and holding chambers are sometimes provided by some HMOs
    and covered by some insurers.

    Contributed by:  Mark Feblowitz                [email protected]

    [Maintainer's note:  Some spacers seem to be prescription only,
         while others are not.  Whether you need a prescription also
         seems to vary from state to state in the US.  When in doubt,
         ask.  As to why you would need a prescription (i.e.  how
         could you abuse this simple plastic tube?), the nurses at
         National Jewish were as puzzled as I was.]


2.3.3  What is "thrush mouth" and how can I avoid it?
-----------------------------------------------------

    Thrush, or thrush mouth, is the popular term for a yeast
    infection (candida albicans) in the back of throat.  The major
    symptom of thrush is a white film located at the back of the
    throat and tonsil area.  It is usually cured by the use of an
    antifungal mouthwash.

    Thrush is a very common side effect of taking inhaled
    corticosteroids, since steroids alter the local bacteria and
    fungal population of the mouth, enhancing fungal growth.  The
    way to avoid this complication is to ensure that the back of
    the throat doesn't remain coated with corticosteroid after use
    of the inhaler, either by using a spacer or by rinsing the mouth
    very thoroughly afterwards.  Unfortunately, some people still
    get it even when they are very thorough about rinsing.


2.3.4  Is Fisons still making the Intal Spinhaler?
--------------------------------------------------

    In the US, Fisons is no longer manufacturing either the
    Intal Spinhaler (a dry powder inhaler for cromolyn sodium)
    or the capsules for it.  However, the Spinhaler and capsules
    are still available in Canada and the United Kingdom.  For
    further information,  Fisons Corporation's number in the US
    for Rx Customer Service is (800) 334-6433.


2.3.5  What's the difference between Spinhalers and Rotahalers?
---------------------------------------------------------------

    [Maintainer's note:  the Rotahaler is a dry powder inhaler
    for Ventolin (albuterol), manufactured by Allen & Hanburys,
    while the Spinhaler is a dry powder inhaler for Intal
    (cromolyn sodium), manufactured by Fisons Corporation. ]

    The Rotahaler and the Spinhaler are very different animals.
    The Rotahaler is a pussycat, the Spinhaler a ferocious lion.

    The Rotahaler is a two-part mouthpiece that you snap apart,
    put a capsule in, twist, and inhale.  When you twist the device,
    the capsule breaks open.  When you inhale, the medicine lands
    in your lungs.

    The Spinhaler is a three-piece device: a mouthpiece, a tiny
    fan, and a cap to cover the fan.  You open it, put the capsule
    in a space on the fan, close it, push down then up on the cap
    (this breaks the capsule) and then tilt your head back, put
    the mouthpiece in your mouth, and inhale.  The fan throws the
    medicine into the back of your throat.  Then you gag.

    I don't like the propellants in MDIs, so I was highly motivated
    to get a Spinhaler.  It took me a month to get my drugstore to
    find it, and now I must admit I'm disappointed.  I tried using
    an Intal capsule in the Ventolin Rotahaler, since that device
    works so well, but the medicine seems to be of the wrong
    consistency, and the capsule is too large for the space it
    should go into.

    Another difference: The Spinhaler comes in a little container
    like a medicine bottle, but the lid doesn't stay on very well in
    a purse.  The Rotahaler comes in a little plastic case sort of
    like a compact and stays shut (i.e. clean) in a purse, backpack,
    or jeans pocket.

    Contributed by:  Paula Ford                    [email protected]


2.3.6  Why are so many asthma drugs taken via inhaler?
------------------------------------------------------

    Medications taken orally almost always have a much higher
    systemic concentration (concentration in your entire body)
    than inhaled medications.  So if the side effects are due
    to systemic concentrations, then an inhaled drug is less
    likely to have these side effects, or may have them much
    less severely.

    The idea behind an inhaler is that the full dose is delivered to
    the lungs, where it is immediately absorbed by the lung tissue,
    and starts to take effect locally.  Excess drug may be absorbed
    by the bloodstream and delivered to the rest of your body, but
    this amount tends to be minimal.  So your lungs receive an
    immediate, high concentration of the drug, and the rest of your
    body receives very little.

    If you take the drug orally in tablet or capsule form, then you
    need a much higher dose.  The reason is that for the same amount
    of drug to reach the lungs through the bloodstream, you need the
    same concentration of drug in the rest of your body.  For example,
    most people take one or two puffs of albuterol (Ventolin or
    Proventil) every four to six hours, and each puff is 90 micrograms
    of albuterol.  The usual dosage of Ventolin in tablets is 2-4
    milligrams three or four times a day, which is something like 200
    times the amount inhaled.

    However, one advantage that tablets have is that the medication
    may be available in a time-release format.  So for a short-acting
    medication like albuterol, the inhaled version might need to be
    taken every four to six hours, while a extended-release tablet
    such as Volmax would need to be taken only every twelve hours.


2.3.7  How can I tell when my MDI is empty?
-------------------------------------------

    The float test (in which you take the MDI canister out of the
    mouthpiece and place it in a container of water to see if it
    sinks) is no longer the recommended way to determine whether
    your MDI (metered dose inhaler) is empty.  Glaxo, the
    manufacturer of Ventolin and Beclovent, claims that the float
    test is inaccurate, and recommends that doses be counted instead.
    Other manufacturers agree:  the triamcinolone acetonide (Azmacort)
    package insert recommends dose counting also and the cromolyn
    sodium (Intal) inhaler package insert states that the metal
    cylinder should never be immersed in water.  The number of doses
    per canister should be clearly written on the canister label.

    One variation of dose counting, for medications that are taken
    regularly, is to calculate the date on which the medication will
    be used up, and discard the old canister for a new one on that date.

+    There is also a gadget called The Doser. It fits on top of any MDI,
    and keeps track of how many doses you've dispensed from the inhaler.
    It provides daily totals for the past 30 days, and is useful if
    (like me) you tend to forget whether you've taken your maintenance
    inhalers already!  See http://www.doser.com for more information.
    The Doser is over the counter, but the units can be hard to locate -
    if a drugstore can get them at all, the pharmacist usually has to
    special order them.

2.3.8  Are my aerosol inhalers going to disappear?
--------------------------------------------------

As you may know, CFC (chlorofluorocarbon) chemicals, which are used as
propellants in aerosol products including asthma inhalers (MDIs), damage
the ozone layer.  As a result, there has been a worldwide ban on the
production of these chemicals for all but essential uses.

Products which relied on CFCs, such as air conditioning units,
refrigerators, and most aerosol products, have been modified to use
alternative chemicals which do not damage the ozone layer.  Due to their
nature, however, metered dose inhalers have been granted an "essential
use" exemption to the worldwide ban, which grants the manufacturers an
extra few years to develop alternatives.

Since the inactive ingredients (i.e., everything but the drug itself)
must be changed, it's not as simple as using a different chemical for the
propellant - the new device must go through much the same approval
process as the original inhaler did, to ensure that the same dosage is
delivered to the patient, that there are no side effects, that patients
tolerate the new formulation well, etc.

The FDA has already approved one new non-CFC inhaler, Proventil HFA
(albuterol), which uses hydrofluoralkane instead of CFC propellants.
Other non-CFC devices are currently in the works.  It is expected that
future non-CFC inhalers may be reviewed and approved more quickly than
the earlier ones.

CFC-based MDIs will continue to be available for some time.  Proposed
guidelines for final phaseout include that there be at least 3 multi-use
(see below) non-CFC devices available in a drug class (i.e.,
bronchodilators, corticosteroids), providing at least 2 different drugs,
before all CFC inhalers in that class are banned.  As an example,
CFC-based bronchodilators would be permitted as long as Proventil HFA is
the only alternative; if Ventolin (also albuterol) and Alupent
(metaproterenol) had non-CFC versions, then all CFC formulations might be
banned.

The term "multi-use" refers both to aerosol inhalers and multi-use
dry-powder inhalers such as the diskhaler.  It does not include
single-use dry-powder inhalers such as the rotahaler, which requires
insertion of a new capsule of medication with each use.


2.4  What kinds of tablets are there?
-------------------------------------

    CR  - controlled release.  This means that the drug has a
          constant rate of release.
    DR  - delayed release.  This generally refers to enteric-
          coated tablets which are designed to release the drug
          in the intestine where the pH is in the alkaline range.
    ER  - extended release.  Dosage forms which are designed to
          release the drug over an extended period of time, such
          as implants which release the drug over a period of
          months or years.
    SA  - sustained action.  Used interchangeably with CR
          (above), except that SA usually refers to the
          pharmacologic action while CR refers to the drug
          release process.
    TD  - time delayed.  This is slightly different from DR in
          that the drug release is designed to occur after a
          certain period of time, such as pellets coated to a
          certain thickness, multi-layered tablets, tablets
          within a capsule, or double-compressed tablets.

    Contributed by:  Susan Graham                  [email protected]


2.4.1  Why do I need a blood test when taking theophylline?
-----------------------------------------------------------

    Theophylline is commonly used as a third-line agent in the
    management of asthma, after beta-agonists and anti-inflammatories.
    Unfortunately, its therapeutic level is quite close to its toxic
    level.  This means that the dose that the asthmatic needs to get
    the full benefit of the drug is not very much lower than the dose
    which causes side effects which range from unpleasant to
    dangerous.  This would not be such a problem if there weren't
    such large variations in the rate at which people metabolize
    theophylline.  Apparently, if a group of people are given
    the same dose of theophylline, the concentration of the
    drug in their bloodstreams may vary by up to a factor of
    seven.  Therefore, the best way to monitor that the asthmatic
    is receiving the optimal amount of theophylline is to take
    a blood level concentration.


2.4.2  Why are combination pills not commonly prescribed?
---------------------------------------------------------

    The combination drugs such as Tedral and Marax commonly
    contain theophylline, ephedrine, and some form of sedative
    such as phenobarbital.  These combination pills are no longer
    commonly prescribed because the amount of theophylline in
    the pill cannot be varied with respect to the other drugs.
    Since there is great variation in the rate at which an
    individual metabolizes theophylline, it is now considered
    better to take theophylline separately, for better adjustment
    of theophylline levels.  In fact, Tedral is no longer
    manufactured by Parke-Davis in the U.S.

    Also, ephedrine is no longer considered the bronchodilator
    of choice.  From Drs. Haas, _The Essential Asthma Book_,
    "ephedrine initiates the release of catecholamines -- including
    adrenaline -- that are already stored in the body.  This is
    its biggest drawback.  Its effects depend on the availability
    of catecholamine in the body at the time it is given, and
    these concentrations vary."  Since much better bronchodilators
    are now available, ephedrine is no longer commonly prescribed.


2.5  What is a nebulizer?
-------------------------

    A nebulizer is a device that uses pressurized air to turn a
    liquid medication into a fine mist for inhalation.  If you've
    ever received emergency treatment for asthma, they've probably
    used a nebulizer on you.

    The term nebulizer is often used to describe both the pump
    that pressurizes the air, and the part that holds and
    "nebulizes" the medication.  There are hand-held nebulizer
    units and ones with masks that you strap onto your face.

    The pressurized air typically comes from a portable pump unit
    that internally consists of a motor-driven air pump that
    resembles the fancier types of aquarium pumps.  It forces air
    through a plastic tube into the plastic nebulizer unit.  Inside,
    the nebulizer unit acts much like a perfume atomizer, creating
    a fine mist that is directed either through a tube that you
    inhale through or a mask that directs the mist into your nose
    and mouth.

    Since the nebulizer takes a few minutes to deliver the medication,
    you inhale it over a longer period of time than if you were using
    an inhaler.  This can really help, especially if your passages are
    not fully open and you're taking a bronchodilator.  As you breathe
    the medication, your lungs can gradually accept more and more of
    the medication.  In addition to the medication, many people find
    the accompanying mist (typically a sterile saline solution) to be
    soothing.

    For very young children, the nebulizer is the only practical
    means of administering inhaled medications.  Older children and
    adults have the options of using inhalers and a variety of
    spacers to make the timing a bit easier.  The doctor overseeing
    the treatment decides which is the most effective/appropriate
    delivery mechanism.

    At least in Massachusetts, the nebulizer pump unit, the
    hand-held nebulizers, the medications, and the sterile saline
    inhalation solution are all prescription items.  Replacement
    parts for the pumps are not available to the general public
    (if there are sources, I'd like to hear about them).

    The portable nebulizer pump units cost little ($100-$300)
    relative to the cost of an emergency room visit, so some health
    plans / insurers provide them to patients for times when an
    asthma episode is "manageable but not dangerous." This seems to
    be a trend in the management of pediatric asthma.

    Our family has been able to successfully avoid a few trips to
    the ER, and have even been able to head off some more severe
    allergic asthma episodes with early intervention.  After a few
    rather gruesome visits to the Mass. General Hospital's waiting
    room on a Saturday night, we welcome opportunity to treat our
    children at home, when it's safe.  We tend to go in to the doctor
    or ER for the more severe episodes or those that don't respond
    well enough to early intervention.

    Contributed by:  Mark Feblowitz                [email protected]


2.6  What medications should asthmatics be careful about taking?
----------------------------------------------------------------

    Aspirin can trigger an asthma attack in approximately one in
    five asthmatics.  This is especially common in those asthmatics
    who also have nasal polyps.  As acetominophen (Tylenol), also
    known as paracetamol overseas, doesn't have this effect, it may
    be used as an alternative for anyone who suspects that they might
    have aspirin sensitivity.

    Cough medicines should also be treated with caution.  In general,
    suppressing a productive cough (one which is bringing up mucus)
    is not a good idea, since the mucus can obstruct the airways
    and also irritate them further.  Also, in _Asthma:  Stop
    Suffering, Start Living_, the authors caution that "prescription
    cough suppressants (including those with codeine) are potentially
    dangerous for asthmatics.  They may make you sleepy and reduce
    your breathing effort.  They may also dry out your secretions,
    making mucus harder to raise."

    Antihistamines, however, should not pose a problem for most
    asthmatics, in spite of many warning labels.  In _Children with
    Asthma_, Dr. Plaut states, "Most asthma experts see no problems
    with using antihistamines between or during asthmatics . . .
    Theoretically these drugs might dry up the mucus in the
    windpipes, thus making it harder to cough it up, but this has
    never been proved."

    Asthmatics taking theophylline should be careful when taking any
    of the following medications:  the ulcer medications cimetidine
    (Tagamet) and troleandomycin (TAO), beta-blocker drugs such as
    propranolol, and the antibiotics erythromycin and ciprofloxacin.
    These medications may increase the concentration of theophylline
    in the bloodstream, possibly even to the toxic level (see
    section 2.4.1).  People taking theophylline should be alert for
    signs of possible toxicity such as rapid or irregular heartrate,
    nervousness, or nausea, when taking these medications.  In fact,
    asthmatics taking theophylline should check with their physician
    before taking any OTC medication, as the list of drugs, including
    antihistamines, which affect theophylline levels is almost
    endless.

    Beta-blockers, usually taken for hypertension, can pose problems
    even for those asthmatics not taking theophylline.  Beta-blockers
    work by blocking the hormone adrenalin, but as adrenalin and
    other adrenergic drugs help keep airways dilated, the use of
    beta-blockers may aggravate asthma symptoms.


2.6.1  What about corticosteroids and chicken pox?
--------------------------------------------------

    According to the pamphlet "Advice from your Allergist", published
    by the American College of Allergy & Immunology, children taking
    oral or injected corticosteroids may be at increased risk of
    complications from chicken pox.  Such children should avoid
    exposure to chicken pox -- if the child has been exposed, their
    physician should be notified.  However, the child's medications
    shouldn't be changed without advice from their physician, since
    corticosteroid therapy should not be stopped abruptly.

    Children taking inhaled corticosteroids are not at this increased
    risk, according to the pamphlet, since the system concentrations
    of the medication are so small.


======================================================================

3.0  What resources are there for asthmatics?
---------------------------------------------

    Please see the alt.support.asthma Reading/Resource List.  It
    is maintained by Lynn Short <[email protected]>, and is
    posted periodically to alt.support.asthma, alt.med.allergy,
    sci.med, and misc.kids.  I highly recommend it!

    I also strongly recommend the following guidelines:  the
    "Global Initiative for Asthma", the "NHLBI Executive Summary:
    Guidelines for the Diagnosis and Management of Asthma", and
    the "Executive Summary:  Management of Asthma during Pregnancy"
    (full citations in References section).  They may be ordered
    in the U.S. by calling (301) 251-1222 and asking for publication
    numbers 95-3659, 94-3042A, and 93-3279A, respectively.  When I
    ordered them, and asked that they be sent to a US address, there
    was no charge.

    Another set of guidelines which has been recommended to me but
    which I haven't seen myself yet is "NAEPP.  Nurses:  Partners
    in Asthma Care", publication number 95-3308, which I assume is
    also available at the number given above.

    The newsgroup misc.kids also has an allergy and asthma FAQ,
    which is available either by following the instructions
    posted on misc.kids.info, or by accessing the World Wide Web,
    <URL: http://www.cs.unc.edu/~kupstas/FAQ.html>.

    In addition, I maintain an Asthma and Allergy WWW Resources Page,
    <URL: http://www.cco.caltech.edu/~wrean/resources.html>, and
    two FAQs on allergies.  For information on how to access these
    allergy FAQs, please see section 3.1.


3.1  Where can I get the latest copy of the FAQs?
-------------------------------------------------

    The two asthma FAQs I maintain,
         alt.support.asthma FAQ:  Asthma -- General Information
         alt.support.asthma FAQ:  Asthma Medications
    are posted once a month, on or about the 17th, to the following
    newsgroups:  alt.support.asthma, alt.med.allergy, sci.med,
    alt.answers, sci.answers, and news.answers.

    If these FAQs have already expired at your site, you can get
    them by sending mail to [email protected], with a blank
    subject line, and with one or more of the following commands
    in the message:

         send usenet/news.answers/medicine/asthma/general-info
         send usenet/news.answers/medicine/asthma/medications

    Alternatively, if you're really in a hurry, you can get them via
    anonymous ftp from rtfm.mit.edu, with the path names:

         /pub/usenet/news.answers/medicine/asthma/general-info
         /pub/usenet/news.answers/medicine/asthma/medications

    The general information FAQ is also available in html format on
    the World Wide Web, at
    <URL: http://www.radix.net/~mwg/asthma-gen.html>; a plaintext
    version of the FAQ is at http://www.radix.net/~mwg/asthma-gen.txt.

    Of the two allergy FAQs I maintain,
         alt.support.asthma FAQ:  Allergies -- General Information
         alt.support.asthma FAQ:  Allergy Medications
    the first is still under construction.  The second is posted
    monthly to the following newsgroups: alt.support.asthma,
    alt.med.allergy, sci.med, alt.answers, sci.answers, and news.answers.

    If the allergy medication FAQ has already expired at your site, you
    can get it by sending mail to [email protected], with a blank
    subject line, and with the following command in the message:

         send usenet/news.answers/medicine/allergy/medications

    Alternatively, if you're really in a hurry, you can get it via
    anonymous ftp from rtfm.mit.edu, with the path name:

         /pub/usenet/news.answers/medicine/allergy/medications


3.2  What is an FAQ, anyway?  What is a Usenet newsgroup?
---------------------------------------------------------

    The term FAQ is an acronym which stands for Frequently Asked
    Questions.  Often the term is also used for any document, such
    as this one, which attempts to answer questions which are
    frequently posted to a specific Usenet newsgroup.  For example,
    this is one of the three alt.support.asthma FAQs which attempt
    to answer questions frequently posted to the newsgroup
    alt.support.asthma.

    A newsgroup is a world-wide electronic forum of discussion which
    generally takes place over the Internet, each newsgroup having
    its own topic of discussion.  For more information about FAQs and
    newsgroups in general, I recommend any of the periodical postings
    in the newsgroup news.announce.newusers, particularly
    "FAQs about FAQs" and "What is Usenet?"  These last two may also
    be accessed by sending mail to [email protected], with a
    blank subject line, and with one or both of the following commands
    in the message:

         send usenet/news.answers/faqs/about-faqs
         send usenet/news.answers/usenet/what-is/part1

    Alternatively, if you're really in a hurry, you can get them via
    anonymous ftp from rtfm.mit.edu, with the path names:

         /pub/usenet/news.answers/faqs/about-faqs
         /pub/usenet/news.answers/usenet/what-is/part1


+3.3  How about some other WWW links?
---------------------------------------------------------
    The original Asthma Resources page that Pat maintained is temporarily
    unavailable. In the meantime, I'm compiling a list of a few
    sites whose URLs I have handy. As with any website, these are
    not intended to substitute for competent medical advice, nor
    do I vouch for the currency or accuracy of information on these
    sites.

         http://asthma.about.com
         http://www.virtualdrugstore.com
         http://www.cs.unc.edu/~kupstas/FAQ.html
         http://nationaljewish.org
         http://www.vh.org/Providers/ClinGuide/AsthmaIM/staging/chronic/classif.html
         http://www.pslgroup.com
         http://www.srs.org.uk
         http://www.gpiag-asthma.org/asthma/GPIAG/welcome.htm
         http://www.nhlbi.nih.gov/index.htm
         http://www.nhlbisupport.com/asthma/index.html



======================================================================

List of Contributors:
---------------------

 Kevin Ball                                        [email protected]
 Betty Bridges                                    [email protected]
 Mark Delany                              [email protected]
 Mark Feblowitz                                    [email protected]
 Bill Ellis Fleenor                              [email protected]
 Paula Ford                                        [email protected]
 Lyn Frumkin, M.D., Ph.D.                     [email protected]
 Joe Gems                                              [email protected]
 Susan Graham                                      [email protected]
 Gwenith Jones                                     [email protected]
 Philip D. Mayo, M.D., FCCP                     [email protected]
 Judith B. Paquet, R.N.                                [email protected]

======================================================================

References:
----------

The Physicians' Desk Reference is published annually by:
    Medical Economics Data Production Company
    Montvale, NJ 07645-1742
    ISBN 1-56363-061-3
    It is a compendium of official, FDA-approved prescription
    drug labeling.  The FDA is the U.S. Food and Drug Administration.


The Compendium of Pharmaceuticals and Specialties is published
    annually by:
    Canadian Pharmaceutical Association
    Ottawa, Ontario, Canada  K1G 3Y6
    ISBN 0-919115-94-2


Robert Berkow, M.D., editor in chief, _The Merck Manual of Diagnosis
    and Therapy_, 15th ed., (Merck & Co., Inc., USA) 1987.
    ISBN 0911910-06-09
    The Merck Manual provides an overview of the diagnosis and
    therapy of the whole range of medical disorders that can occur
    in infants, children, and adults.  I am told that the 16th
    edition is now available, with ISBN 0911910-16-6, and that
    the 17th edition should be available sometime in 1997.


"Global Initiative for Asthma:  Global strategy for Asthma Management
    and Prevention.  NHLBI/WHO Workshop Report.  March 1993",
    National Institutes of Health/NHLBI, Publication No. 95-3659,
    January 1995.

    These are often called the "GINA Guidelines".


National Asthma Education Program Expert Panel Report, "Executive
    Summary:  Guidelines for the Diagnosis and Management of Asthma",
    U.S. Department of Health and Human Services, Public Health
    Service, National Institutes of Health, Publication No. 94-3042A,
    Reprinted July 1994.

    Often called the "NHLBI Guidelines", this is a summary of the
    current wisdom on asthma treatment and prevention for physicians.
    I found it very readable.

    The above report, written in 1991, has now been superseded by:

 National Asthma Education and Prevention Program Expert Panel Report 2:
    Guidelines for the Diagnosis and Management of Asthma (revised
    6/18/97)

    This report provides clinicians with recommendations for the
    diagnosis and management of asthma.  These recommendations are
    organized into four components of therapy: measures of assessment
    and monitoring, control of factors contributing to asthma severity,
    pharmacologic therapy, and education for a partnership in asthma care.
    The recommendations are an update of the 1991 Expert Panel Report.

    The report can be accessed directly from
       http://www.ama-assn.org/special/asthma/treatmnt
           /guide/guidelin/guidelin.htm


Report of the Working Group on Asthma and Pregnancy, "Executive
    Summary:  Managment of Asthma during Pregnancy", National
    Institutes of Health/NHLBI, Publication No. 93-3279A, March 1993.


The American College of Allergy & Immunology, (ACAI), publishes a
    pamphlet titled "Advice from your Allergist."  It may be
    ordered from:

    ACAI
    85 West Algonquin Road, Suite 550
    Arlington Heights, IL  60005
    (708) 427-1200


+ Michael R. Freedman, Samuel J. Rosenberg, Cynthia L. Divino
    Living Well With Asthma (Guilford Press, USA) 1998.
    ISBN 1572303182 hardback, 1572300515 paperback
    The authors are former associates of National Jewish
    Medical and Research Center.


M. Eric Gershwin, M.D., and E.L. Klingelhofer, Ph.D., _Asthma:
    Stop Suffering, Start Living_, 2nd ed.,  (Addison-Wesley, USA) 1986.
    ISBN 0-201-60847-2
    The first author is Chief of Allergy and Immunology, University
    of California, Davis, Medical School.  He is board-certified
    in internal medicine, allergy, and clinical immunology.


Drs. Francois Haas and Sheila Sperber Haas, _The Essential Asthma
    Book_, (Ballentine Books, USA) 1987.
    ISBN 0-8041-0287-2
    Dr. Francois Haas is the director of the Pulmonary Function
    Laboratory at the Medical Center of the New York University
    School of Medicine, and is on the faculty of the Department
    of Physiology there.


Paul J. Hannaway, M.D.  _The Asthma Self Help Book:  how to live a
    normal life in spite of your condition_, 2nd ed., (Prima
    Publishing, USA) 1992.
    ISBN 1-55958-166-2, 1-55958-434-3 paperback
    The author is Assistant Clinical Professor of Tufts University
    School of Medicine.  The first edition of this book won an
    American Medical Writers Association Award.


Glennon H. Paul, M.D. and Barbara A. Fafoglia, _All About Asthma
    & How to Live with It:  the complete guide to understanding and
    controlling asthma_, (Sterling Publishing Co., NY, USA) 1988.
    ISBN 0-8069-6808-7, 0-8069-6809-5 paperback
    Dr. Paul is the medical director of respiratory therapy at
    St. John's Hospital in Springfield, Illinois, and specializes
    in allergy and respiratory diseases.


Thomas F. Plaut, _Children with Asthma -- A Manual for Parents_,
    (Pedipress, Inc., Amherst, Massachusetts, USA) 2nd edition 1995.
    ISBN 0-914625-03-9


Richard N. Podell, M.D. and William Proctor, _When Your Doctor Doesn't
    Know Best:  medical mistakes that even the best doctors make --
    and how to protect yourself_, (Simon & Schuster, USA) 1995.
    ISBN 0-671-87112-9


Nancy Sander, _A Parent's Guide to Asthma_, (Doubleday, USA) 1989.
    ISBN 0-385-24478-9
    The author is the founder of Mothers of Asthmatics.


Genell Subak-Sharpe, _Breathing Easy -- A Handbook for Asthmatics_,
    (Doubleday, NY, USA) 1988.
    ISBN 0-385-23440-6
    This book was written in consultation with the National Jewish
    Center for Immunology and Respiratory Medicine.


Allan M. Weinstein, M.D., _Asthma - The Complete Guide to Self-
    Management of Asthma and Allergies for Patients and their
    Families_, (Fawcett Crest, NY, USA) 1987.
    ISBN 0-449-21562-8
    The author is Assistant Clinical Professor of Medicine at
    Georgetown University, and is a board-certified allergist who
    practices in Washington, D.C.


Stuart H. Young, M.D. with Susan A. Shulman and Martin D. Shulman,
    _The Asthma Handbook -- A Complete Guide for Patients and Their
    Families_, (Bantam Books, USA) 1985.
    ISBN 0-553-24797-2
    Dr. Young is the Chief of Allergy Clinics in both the Department
    of Medicine and Department of Pediatrics at the Mount Sinai
    Medical Center.  He is also a clinical assistant professor of
    Medicine and a clinical associate professor of Pediatrics at the
    Mount Sinai Medical School.

 Francis V. Adams, MD, _The Asthma Sourcebook_ (Lowell House, Los Angeles
    CA) 1996
    ISBN 1-56565-471-471-4
    Dr. Adams is an award-winning pulmonary specialist in the field of
    asthma.  He is currently Assistant Professor of Clinical Medicine at
    New York University and Attending Physician at Bellevue Hospital in
    New York.

The following citations were used in compiling the
                       Occupational Asthma section:
    O'Neil, CE:  Review: Mechanisms of Occupational Airways Diseases
    Induced by Exposures to Organic and Inorganic Chemicals. Am j Med Sci
    1990; 299(4) 265-275

    Bernstein, DI: Respiratory Sensitization to Chemical Allergens.
    Masters in Allergy Vol 1, (1) 17-21

    Grammer, LC: Occupational Asthma. Immunology and Allergy Clinics
    of North America Vol 13 (4) Nov 1993 769-783

    Chan-Yeung, M: A Clinician's Approach to Determine the Diagnosis,
    Prognosis, and Therapy of Occupational Asthma. Medical Clinics of
    North America Vol 74 (3) May 1990 811-822


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Disclaimer:  I am not a physician; I am only a reasonably
            well-informed asthmatic.  This information is for
            educational purposes only, and should be used only as
            a supplement to, not a substitute for, professional
            medical advice.

Copyright 1996 by Patricia Wrean, 1997-2000 by Marie Goldenberg.  Permission is
given to freely copy or distribute this FAQ provided that it is
distributed in full without modification, and that such distribution is
not intended for profit.

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