Metered-dose Inhalers

A metered-dose inhaler (MDI) uses an aerosol canister to deliver asthma medication to your lungs.  Newer, non-CFC-containing MDIs have been introduced and are available.

To enhance the ability of an MDI to effectively deliver medication to your lungs, a spacer is often used.  This short tube, attached to the end of the MDI mouthpiece, holds the medication until you inhale.  Spacers help minimize the coordination problems associated with the use of MDIs.

If may take a little practice to get used to using an inhaler.  By following these steps, you will soon be comfortable – and will be confident that you are getting the most exact dosage of medicine possible.

• Shake well.   Before each dose, shake the inhaler gently but thoroughly.
• Remove cap .  A flexible strap will keep the cap attached to the inhaler, even when the mouthpiece is exposed.  If the cap becomes lost, be sure to inspect the mouthpiece for dust, lint, or other foreign objects before using the inhaler.  As with other aerosol medications, it is a good idea to test-spray your inhaler before using it.  The instructions that come with the unit will tell you how to do this.
• Breathe out.   Stand up, or sit up straight.  Breathe out through your mouth.  Place the mouthpiece of the inhaler in your mouth and close your lips around it tightly.  (Be sure that your tongue does not block the opening of the mouthpiece.)  TIP:  Some people find it is easier to inhale the medication if they hold the mouthpiece about 2 inches away from their open mouth.  If you still have trouble, ask your doctor for a spacer.
• Breathe in .  Take a slow, deep breath through your mouth, while you press down firmly on the top of the metal canister with your finger.
• Hold your breath .  Try to continue inhaling after the puff of medicine is delivered.  Then try to hold your breath while you count to 10.  Remove the mouthpiece and release your finger from the canister before breathing out.
• Wait 30 seconds .  Most inhaler medications require 2 doses or “puffs”.  Wait about 30 seconds after your first inhalation before you take the next one.  Be sure to shake the inhaler between doses.
• Replace cap .  Make sure the cap is firmly reattached to keep the mouthpiece clean.
• Clean inhaler .  Remove the metal medication canister and clean the plastic inhaler and cap at least once a day.  Rinse them with warm, running water and dry both pieces thoroughly.  Replace the medication canister with a gentle twist.
• Discard canister .  Always discard the canister immediately after taking the number of doses specified in the product information included with your inhaler.  While it may seem that there are more doses available, this is because there is aerosol propellant left in the canister; it may make a “puff” of vapor, but the vapor will not have the right amount of medicine in it.
• Inhalation powder delivery systems .  Inhalation powder delivery systems represent an important alternative to traditional MDIs.  This new type of device is breath-activated, using your inspiratory breath (inhalation) to deliver medication to your lungs.  This minimizes coordination problems many patients encounter when using traditional MDIs. Breath-activated delivery technology is available in a variety of devices, each with its own specific instructions for use.

*Adapted from Glaxo Wellcome Inc. 2000