Asthma & Inhaled Steroids


"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.


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.