A metered dose inhaler (MDI) delivers a specific amount of medicine. This makes it possible to inhale the medication, instead of taking it in pill form. MDI's are commonly used to treat asthma, COPD, and other respiratory conditions.
Take off the cap and shake the inhaler hard. Note, that many inhalers need to be "primed" before using them when they are new or haven't been used in a while. Priming means spraying the inhaler into the air (not into your mouth or spacer). This ensures adequate mixing of the drug in the canister. make sure to follow the directions that come with the MDI.
Breathe out all the way.
Hold the inhaler 1 - 2 inches in front of your mouth (about the width of two fingers).
Start breathing in slowly through your mouth, and then press down on the inhaler one time. Breathe in slowly, as deeply as you can.
Slowly count to 10 while you hold your breath (if you can). This lets the medicine reach deep into your lungs.
If your doctor prescribed more than one puff of medicine, repeat this procedure, starting with step 2. For inhaled quick-relief medicine (beta-agonists), wait about one minute between puffs. There is no need to wait between puffs for other medicines.
Rinse your mouth afterward to help reduce unwanted side effects.