Metered-Dose Asthma Inhalers
As we mentioned in our first inhaler article, there are two kinds of asthma inhalers. The first category is the metered-dose inhaler, called MDI for short. MDIs are one of the most common devices used to relieve asthma.
According to a WebMD article:
A metered-dose inhaler (MDI) is a handheld device that delivers a measured dose of medication directly to the lungs. The medication is usually in an aerosol form.
This medication is pushed out of the MDI and delivered straight to the lungs by a chemical gas propellant [3,4].
From CNN.com:
These inhalers include a pressurized canister with measured doses of medication inside. Squeezing the top of the canister converts the medication into a fine mist. Some metered-dose inhalers are breath actuated and don’t require you to squeeze the inhaler. You place your lips on or near the inhaler’s mouthpiece to inhale the mist.
The metered-dose inhaler has five parts: the propellant, the metering valve, the mouthpiece, the canister containing the medication, and the medication itself. A plastic holder usually forms the frame of the MDI. (A visual representation can be found at Asthma.ca.)
Wikipedia cites that all asthma patients age 5 and older can use MDIs, as stated by the American Medical Association. Fast-acting medication delivered through MDIs only take 5-10 minutes to have an effect, which is a big boon for asthma sufferers.
Despite the frequency of MDI use, some people have trouble using the device, chiefly because of the need to coordinate two actions. The first is the pressing of the canister, and the second is the inhalation of the medication. A device called a spacer eases this difficulty.
Next: How to properly use a metered-dose asthma inhaler.
Sources:
- 1. Wikipedia article on MDI
- 2. WebMD.com
- 3. Asthma.com
- 4. CNN.com (Mayo Clinic special)
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This entry was posted on Thursday, May 18th, 2006 at 7:06 pm and is filed under Asthma Inhalers. You can subscribe via RSS 2.0 feed to this post's comments. You can comment below, or link to this permanent URL from your own site.
May 19th, 2006 at 2:53 am
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June 5th, 2006 at 9:01 pm
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June 5th, 2006 at 9:54 pm
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June 12th, 2006 at 12:26 am
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