If you're having an asthma attack, you assume that with each puff of your inhaler you are getting relief. But, in many cases, it seems inhalers are being used long after they have run out of medication.
Asthma inhalers, or portable pressurized metered-dose inhalers (pMDIs), are the cornerstone of asthma treatment. But a new study reveals that patients using pMDIs do not know how to monitor the number of puffs they have taken out of their inhalers. Some didn't realize they needed to monitor their inhalers at all.
This presents a problem because every pMDI is filled with either 200 or 400 "puffs" of a bronchodilator, a medication used to open the airways and help breathing during an asthma attack. However, when these full doses are depleted, the inhaler may still "work" in that it still seems to deliver a puff, but those puffs are either greatly reduced in the amount of medication they contain, or are filled with only the propellant left in the canister.
"Although the pMDI is economic and portable, the device does not indicate how much medicine remains inside the canister once the patient starts using it," writes Nancy Sander, lead study author and the founder of Allergy & Asthma Network Mothers of Asthmatics in Fairfax, Virginia.
Noting that asthma patients had no reliable means to gauge how much medication is left in their inhalers, Sander and colleagues conducted telephone interviews with over 500 asthma patients or their families.
Copyright 2009 NBC Health
Click here to read the rest of the article at HealthVideo.com
