Asthma & Inhaled Steroids
Introduction
"Steroids" are a family of chemicals normally made within the body. They
serve as hormones—chemical signals that help to regulate the body's growth and
function. Some steroid hormones, like testosterone, stimulate formation of
protein and growth of muscle. Competitive athletes have been known to take
illicitly derivatives of these "body-building" steroids in large amounts to
improve their athletic performance. A very different group of steroid hormones
are the corticosteroids, steroid hormones made in the cortex (hence, "cortico-")
of the adrenal glands, which sit adjacent to the kidneys. Corticosteroid
hormones have many different affects on body function, including influences on
how we use our energy stores (fat, protein, and sugar) and how we adjust the
salt and water content of our body.
Earlier this century it was discovered that corticosteroid hormones, if
purified and taken in large amounts as a medicine, have powerful
anti-inflammatory effects. Ever since this discovery, corticosteroids have been
used to treat a great variety of diseases where inflammation (not infection and
not cancer) is the major problem—from arthritis to psoriasis to asthma. When you
and your doctor talk about steroids to treat your asthma, it is these
anti-inflammatory corticosteroids about which you are speaking.
Steroids Swallowed or Steroids Inhaled
To treat the inflammation of asthma within the bronchial tubes, steroids can
be taken in tablet or liquid form or by inhalation. Occasionally, steroids are
given by injection or—in hospitalized persons—directly into the veins
(intravenous infusion). Taken as tablets, liquid, injection, or intravenous
infusion, the steroid medication travels in the blood and is carried throughout
the body, including to the bronchial tubes. Used in this way, steroids have
their most powerful effects—both for the good (relieving asthmatic symptoms) and
for the bad (undesirable side effects). On the other hand, modern steroid
medications inhaled from pressurized canisters onto the bronchial tubes act
directly on these tubes; almost no medication is carried into the bloodstream.
Although not as powerful in their immediate effects, steroids by inhalation are
better suited for long-term use in the treatment of inflamed bronchial tubes
because they are free of major undesirable side effects.
Examples of steroids in tablet form are prednisone (Brand name: Deltasone®)
and methylprednisolone (Brand name: Medrol®). Examples of steroids by inhalation
are beclomethasone (Brand names: Beclovent®, Qvar®, and Vanceril®);
triamcinolone (Brand name: Azmacort®); flunisolide (Brand names: Aerobid® and
Aerobid-M®); budesonide (Brand name: Pulmicort®); and fluticasone (Brand name:
Flovent®).
More information about steroids in tablet form is available in a separate
pamphlet prepared by the Partners Asthma Center, entitled,
Asthma and
Steroids in Tablet Form. The remainder of this pamphlet focuses on the use
of steroids by inhalation.
The Concept
Inflamed bronchial tubes are an important part of the problem in asthma. The
cause of the inflammation is not always known, although for many persons a
persistent, low-grade allergic reaction is probably the culprit. If severe
enough, the inflammation and swelling of the bronchial tubes makes it difficult
to breathe, with cough and chest congestion, wheezing and chest tightness. More
recently, it has been learned that even when a person with asthma feels
perfectly well, a mild degree of inflammation keeps the bronchial tubes
hyperreactive, that is, hypersensitive to the triggers of asthma attacks. In
essence, it is this inflammation that keeps the bronchial tubes "asthmatic."
To reduce the inflammation of the bronchial tubes, one can identify and then
seek to avoid those things that stimulate the inflammation, whether it is
cigarette smoke or allergic triggers ("allergens") such as animal danders, dust,
mold, etc. At the same time, one can take anti-inflammatory medications to
reduce the bronchial inflammation. For long-term use these are inhaled
corticosteroids, mast sell stabilizers, cromolyn (Brand name: Intal®);
nedocromil (Brand name: Tilade®); and leukotriene modifiers, such as montelukast
(Brand name: Singulair®) and zafirlukast (Brand name: Accolate®). For many
persons with asthma, inhaled corticosteroids are the most effective of these
currently available anti-inflammatory medications.
 How Inhaled Steroids Are Used
In order for them to be effective, inhaled steroids must be taken every day.
They provide no immediate benefit; on a single day you should not expect to feel
any better immediately after you inhale the medication than before you inhale
it. The benefit of the inhaled steroids comes gradually, usually after about 1
to 2 weeks, although sometimes longer. Then, you should find your asthma
gradually becoming less troublesome—for example, less cough, fewer attacks, less
often awakened at night with asthma, and less often needing your bronchodilator
medications for the quick relief of symptoms. When this happens, it will be
important to continue to take your inhaled steroids every day, otherwise the
benefits usually wear off very quickly and your asthma is likely to become
troublesome again.
Your doctor may ask you to take your inhaled steroids one, two, three, or
four times a day. In general, twice a day works just as well as more frequently
(as long as the total number of inhalations or "puffs" in a day remains the
same). For example, four inhalations taken morning and night are as effective as
two inhalations taken four times a day.
As for any inhaled medication, it is crucially important that you use proper
technique to inhale these medicines deep into your lungs. We do not feel that,
as a routine, you have to use a bronchodilator before taking the inhaled steroid
or that you have to wait one minute between inhalations. In most instances we do
encourage the use of spacer devices with your inhaled steroids. These breathing
aids attach to the steroid inhalers and serve to maximize the amount of steroid
medicine deposited onto the bronchial tubes while minimizing the amount left
behind in your mouth; they are available at most pharmacies. Examples of these
spacer devices are the Aerochamber® and Inspir-ease®; a small spacer is built
directly into the Azmacort® steroid inhaler.
Finding the Proper Dose
Most of the inhaled steroid medicines are prescribed at a dose of 2 to 4
inhalations per day. At times, larger doses are needed and can prove to be very
effective in controlling otherwise difficult-to-control asthma. Once your asthma
has again quieted down, it may be possible to find a lower dose of inhaled
steroids (fewer inhalations per day) to maintain the improvement. Finding the
right dose to keep the asthma under control requires adjusting the dose by
"trial and error," until the lowest dose that maintains good control is found.
The optimal dose of inhaled steroids may change from time to time (for example,
in allergy season versus out of allergy season in the pollen-sensitive person
with asthma). As another example, your doctor may suggest that you increase your
dose of inhaled steroids during an upper respiratory tract infection ("common
cold") and then return to your previous dose when the period of increased
asthmatic sensitivity has passed (usually 1 to 3 weeks).
Undesirable Side Effects
The great advantage of corticosteroids by inhalation is that even with
long-term use (that is, many years) the undesirable side effects associated with
steroids in tablet form (for example, prednisone) do not develop. In
conventional doses, the only potential side effects that you are likely to
encounter are: sore throat, hoarse voice, and a yeast infection in the mouth
(oral candidiasis or "thrush"). This latter infection usually manifests as white
deposits on the tongue and/or roof of the mouth. It can be avoided by rinsing
your mouth with water after each use of the inhaled steroids (the water can be
swallowed or spit out) and by use of the spacers mentioned above. Prescription
medications are available to clear up thrush, should it develop.
When used in high doses, a small amount of the medication is absorbed into
the bloodstream and some side effects beyond the mouth and throat may develop.
The most likely to be encountered are easy bruisability of the skin and
suppression of the adrenal glands. The significance of adrenal gland suppression
is discussed in further detail in the pamphlet entitled
Asthma and
Steroids in Tablet Form, prepared by the Partners Asthma Center. The risk
from the long-term use of inhaled steroids in terms of hastening thinning of the
bones (osteoporosis) is currently being studied. However, it is widely agreed
that any risk that may be discovered will be far less than that resulting from
use of steroids in tablet form in doses needed to achieve the same control of
asthma.
Summary
Asthma is a chronic condition involving persistent inflammation of the
bronchial tubes. Of the medicines available to treat this inflammation, steroids
by inhalation are the most effective without causing the major side effects seen
with long-term use of steroids in tablet form. Because the inflammation of the
bronchial tubes persists even at times when one's asthma is quiet, it is
important to continue to use your inhaled steroids even when feeling well. Your
doctor may advise you as to when it is appropriate to stop your inhaled
steroids; but for many persons with asthma, the asthmatic condition is lifelong
and inhaled steroids should be—and can safely be—continued indefinitely.
Related Links:
10 worst asthma
cities of 2007
- What is Asthma?
- What causes Asthma?
- Diagnosing Asthma
- Signs and symptoms of Asthma
- Can Asthma be prevented?
- Myths and Realities of Asthma
- Exercise Induced Asthma (EIA)
- Childhood Asthma
- Living with Asthma
- How is Asthma treated?
- Personal experiences on Exercise
Induced Brochospasm
- List of Drugs related to Asthma
- Additional resources & web links
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