How to Use A Metered Dosed Inhaler

Inhaled medications are often taken by using a device called a metered dose inhaler, or MDI. An MDI is an aerosol canister filled with medicine. It is in a plastic holder with a mouthpiece. There are two methods for using an MDI. In many cases, the preferred method is with a device called a valved holding chamber (figure 1). These devices attach to the MDI and hold the spray of medication. They make it easier to use the MDI and help get the medication into the lungs better. An MDI can also be used without a chamber (figure 2). These methods are described below. Your health care professional will decide which method is best for you.

Priming: Priming (spraying one or more puffs into the air before use) makes sure that the inhaler is ready to use and will deliver the correct dose of medication. Priming may be different for each medication, so it is important to read the patient instructions that come with your inhaler.

Using an MDI with a valved holding chamber

• Remove the cap from the MDI and chamber.
• Shake well for 5 seconds.
• Insert the MDI into the open end of the chamber (opposite the mouthpiece).
• Breathe out all the way.
• Keep your chin up.
• Place the mouthpiece of the chamber between your teeth and seal your lips tightly around it.
• Press the canister once.
• Breathe in slowly through your mouth to completely fill your lungs. If you hear a horn-like sound, you are breathing too quickly and need to slow down.
• Hold your breath for 10 seconds (count to 10 slowly) to allow the medication to reach the airways of the lung.
• Repeat steps 2-8 for each puff ordered by your doctor. Wait about 1 minute in between puffs.
• Replace the cap on your MDI when finished.
• If you are using a corticosteroid MDI, rinse your mouth and gargle using water or mouthwash after each use. You should always use a chamber with a steroid MDI.

Using an MDI without a chamber

• Remove the cap from the MDI and shake well for 5 seconds.
• Breathe out all the way.
• Keep your chin up.
• Place the mouthpiece of the inhaler between your teeth and seal your lips tightly around it.
• As you start to breathe in slowly, press down on the canister one time.
• Keep breathing in slowly to completely fill your lungs. (It should take about 5 to 7 seconds for you to completely breathe in.)
• Hold your breath for 10 seconds (count to 10 slowly) to allow the medication to reach the airways of the lung.
• Repeat the above steps for each puff ordered by your doctor. Wait about 1 minute between puffs.
• Replace the cap on the MDI when finished.
• If you are using a corticosteroid MDI, you should use a valved holding chamber as described above.

Caring for your MDI and chamber

For some MDIs, you can remove the canister and rinse the plastic holder with warm running water once a week to prevent the holes from getting clogged. Shake well and air dry completely.

There are other medications in which the inhaler cannot be removed from the holder. These usually need to be cleaned by wiping the mouthpiece with a cloth or cleaning with a dry cotton swab. Refer to the patient instructions that come with your inhaler.

Clean the chamber about once a week. Remove the soft ring at the end of the chamber. Soak both the chamber and soft ring in warm water with a mild detergent. Carefully clean, rinse in clear water, and shake well. Allow to air dry completely.

Checking your MDI

It is important that you know how much medication is left in your inhaler. Most inhalers have counting devices built in. Remember to watch the counter and replace the inhaler when the counter is on zero.

• There are a few inhalers that do not have a built-in counter. For these, you must keep track of how many puffs you have used, including priming puffs. The number of puffs contained in your MDI is printed on the side of the canister. If you use an MDI every day for control of symptoms, you can find out how long it will last by dividing the total number of puffs in the inhaler by the total puffs you use every day. For example: 2 puffs x 2 times per day = 4 total puffs per day. If there are 120 puffs, the MDI will last 30 days.
• If you use an inhaler only when needed, keep track of how many times you spray the inhaler.

For convenience, there are counting devices that attach to the inhaler that will keep track of how often your inhaler is sprayed. If you are interested, ask your healthcare professional for more information about these devices, or how to best keep track of your medicine without an add-on device (if you prefer).