Are HFA-propelled quick relief inhalers effective?

In response to reader concerns, I would like to revisit the issue of the efficacy of the new, ‘environmentally friendly' hydrofluoroalkane (HFA) propelled quick relief inhalers, especially albuterol. In accordance with the Montreal Protocol, all chlorofluorocarbon (CFC) propelled prescription single medication quick-relief inhalers will be removed from the market and replaced with other (mostly HFA) propelled inhalers after December 31, 2008.

Many asthma sufferers have noted that they do not get the same quick relief of cough, wheeze, and shortness of breath from HFA-albuterol. The taste and feel of the medication in the mouth is different. One of our readers is worried that the HFA "will not propel the medicine far enough into the lungs to be effective." I would like to address these concerns with the best available evidence on the transition from CFC to HFA inhalers. Individual concerns and response to any medication should be discussed with your doctor or asthma care provider.

How do HFA quick relief inhalers compare to the CFC-propelled ones?

As a background, ozone depleting CFC have been banned from consumer products since 1978. Some people may recall when this was a significant issue for spray hair and deodorant products. The U.S. Food and Drug Administration (FDA) exempted certain medical products that were deemed necessary, until they could become ‘non-essential'. Detailed criteria were put in place for a medical device/product to be designated as no longer essential in CFC format

"These criteria are the following:

• Sufficient non-ODS (Ozone Depleting Substance) alternatives are available with the same indications and approximate level of convenience;
• There is adequate post-marketing data for the alternative products.
• Supplies are adequate to meet the demand;
• Patients who require the product are adequately served."

Essentially, this means that not only are alternative forms of essential medications made available in adequate quantities, but also that these forms have been shown to be effective. Both of these key criteria will have been met by end of 2008.

In some ways, the newer HFA inhalers may be better for getting medication deep into the lungs. Part of the reason that patients are concerned about HFA effectiveness is that they don't feel the same ‘blast' and taste as CFC albuterol. This is in part because the HFA-propelled medication has a smaller particle size -- so more of the medication is inhaled deeper in the lungs and less in the mouth and throat.

I should also clarify the point that all the propellant does in an inhaler is get the medicine out of the canister in a small mist, not drive it into the lungs. That is done by the patient timing their breathing in properly after squeezing the inhaler. Using a chamber or spacer further improves getting the medication into the right place -- the lungs.

The increased cost of HFA-albuterol (and others) to patients has been discussed in an earlier entry.