Breath of Fresh Air: Feature Articles

In the last 2-3 years, several new forms of inhaled corticosteroids have become available for the treatment of asthma. These have included new steroid preparations (fluticasone/Flovent® and budesonide/Pulmicort®), a variety of different concentrations (differences in the amount of medication delivered with each inhalation), and different methods of delivery (metered-dose vs. dry-powder inhalers). How do you and your doctor choose among these different options? Cost, potency, convenience, effectiveness, and frequency of adverse side effects are among the criteria that one might use to make this decision. How do these different medications compare?

The easiest comparison is cost. The table below shows the average retail cost to pharmacists as of early 2003. The cost charged to you varies considerably depending on your pharmacist and your health insurance plan. If your insurance plan covers the cost of your medications, with or without a small co-payment, the relative expense of the different steroid preparations may not be of much direct importance to you.

Five dirrerent inhaled steroid preparations are available to treat asthma. On what basis might one compare them?

Cost.


Concentration.

Potency refers to the strength of the medication to achieve its desired effect — in this case, suppression of the allergic-type inflammation of the bronchial tubes that is an important part of asthma. One could not simply compare one puff of one medication with one puff of another, because each puff contains different amounts of the particular medication. The amount of medication per puff or per single inhalation reflects the concentration of the medication. Some of the inhaled steroids are available in different concentrations, as shown in the Table below.

Potency.


Type of delivery system.


Side effects.

A fair comparison of medication potency might assess the relative benefits, for example, of 200 micrograms/day of beclomethasone compared with 200 micrograms/day of triamcinolone compared with 200 micrograms/day of flunisolide, and so forth. Which medicine would cause the greatest improvement in lung function, reduction in asthmatic symptoms and susceptibility to asthmatic attacks, and decrease in bronchial sensitivity? Only a few clinical studies have been performed to answer this sort of question.

The results seem to suggest that microgram for microgram, fluticasone is the most potent inhaled steroid available. In one direct comparison, fluticasone was equally as effective as twice the dose of beclomethasone, suggesting a potency twice as great. More studies are needed. At the present time, many physicians consider beclomethasone, budesonide, triamcinolone, and flunisolide roughly equally potent. Differences may be present, but they have not yet been clearly demonstrated.

And other considerations.

In fact, medication comparisons are even more tricky. One has to distinguish between the amount of medication released from an inhaler and the amount that actually deposits onto the bronchial tubes. The type of inhaler has an effect (the dry-powder inhalers lead to greater medication deposition on the airways than do the pressurized metered-dose inhalers), as do the use of spacer devices (such as Aerochamber®, Optichamber®, or InspirEase®) and one's ability to coordinate inhalation of the medication properly. Thus, if a study found that 200 micrograms/day of budesonide by dry-powder inhaler were more effective than 200 micrograms/day of beclomethasone by metered-dose inhaler without a spacer, this difference might reflect greater drug potency or a larger portion of the delivered medication actually making its way onto the bronchial tubes.

A still more difficult question to answer is whether for inhaled steroids "more potent" necessarily implies "more side effects." The most feared side effects are those associated with steroids taken by mouth (such as prednisone and Medrol®), including weight gain, insomnia, fluid retention, mood swings, thinning of the skin, cataracts, glaucoma, and osteoporosis. In general, the inhaled steroids in low doses do not cause these adverse effects because they are not absorbed into the blood stream in any significant amounts. At high doses (more than 1000-1500 micrograms/day), some of these undesirable effects are possible [as discussed in Chapter 19, “Asthma Medications and the Eye.”] Are long-term side effects from systemic absorption of the inhaled steroids more likely with the more potent inhaled steroids? This question has yet to be answered, but to date there is no evidence to support this supposition. It may — or may not — be possible to achieve more of the desired effects on the bronchial tubes without causing greater undesirable side effects elsewhere in the body.

All of the inhaled steroids are effective when taken twice daily. For most people, taking a medication morning and night on a regular basis is reasonably convenient, far more so than the routine of four times per day that used to be recommended. Recently, one inhaled steroid (budesonide/Pulmicort®) was approved for once-daily dosing among persons whose asthma was well controlled on a twice-daily regimen. It is likely that in the future other steroid preparations will also gain approval for once-daily use in selected patients. Another convenience provided with one of the inhaled steroids (triamcinolone/Azmacort®) is a built-in spacer device included with each inhaler.

In the end, many factors go into choosing among the inhaled steroids, some based on known differences between the medications, some based on personal preferences. The same is true when choosing among the anti-hypertensive medications used to treat high blood pressure. Often it is necessary to try one of the medications: if it is works well, causes few or no side effects, is convenient and not excessively expensive, you are likely to continue with it. If it fails to meet one or more of these criteria, you and your doctor now have the "luxury" of other preparations to try until you find the one best for you.

40
80

100
100

$.50
$.63

100

240

$.30

250

100

$.71

200
250
500

200
30
30

$1.46
$4.75
$4.75

44
110
220

120
120
120

$.35
$.49
$.68

100
250
500

60
60
60

$1.87
$2.37
$3.25