Metered-Dose Inhaler: How to Use It Correctly

What is a metered-dose inhaler?

A metered-dose inhaler is a device that helps deliver a specific amount of medication to your lungs. It is commonly used to treat asthma, chronic obstructive pulmonary disease (COPD) and other respiratory problems.

Each inhaler consists of a pressurized canister of medication and a mouthpiece. Pressing down on the inhaler releases a mist of medicine that you breathe into your lungs. So that your airways receive the right amount of medicine, it is important to use your inhaler correctly.

How do I use a meter-dose correctly?

Figure A

A. Open mouth. Hold inhaler 1 to 2 inches away.

Figure B

B. Use spacer attached to inhaler.

Figure C

C. Hold inhaler in your mouth Here's what to do:

  1. Remove the cap and hold the inhaler upright.
  2. Shake the inhaler.
  3. Tilt your head back slightly and breathe out.
  4. Hold the inhaler as in one of the pictures to the right. A or B are the most effective, but C is okay for people who are unable to use A or B.
  5. Spacers are useful for all patients, especially young children and older adults (see picture B).
  6. Press down on the inhaler to release the medicine as you start to breathe in slowly.
  7. Breathe in slowly for 3 to 5 seconds.
  8. Hold your breath for 10 seconds to allow medicine to go deeply into your lungs.
  9. Repeat puffs as directed. Wait 1 minute between puffs to allow the second puff to get into the lungs better.

NOTE: These instructions are for a metered-dose inhaler only. Inhaled dry powder capsules are used differently. To use a dry powder inhaler, close your mouth tightly around the mouthpiece of the inhaler and breathe in quickly. Talk to your doctor if you have any questions about how to take your medicine.

How do I keep track of how much medicine I've used?

It's important to keep track of how much medicine you've used so you can plan ahead and replace your inhaler before you run out of medicine. One way to do this is to write a refill date on the canister itself. Use the following method to figure out when you'll need to get a refill:

  • Start with a brand new inhaler. Divide the number of puffs in the canister--the canister will usually have this number printed on it--by the number of puffs you take each day. The number you get will be the number of days the canister should last. (For example, if you take 4 puffs each day from a 200-puff canister, you will need to have a new canister every 50 days.)
  • Using a calendar, count forward that many days to see when your medicine will run out. So you won't run out of the medicine that you use every day, choose a day 1 or 2 days before this date to have your prescription refilled.
  • Using a permanent marker, write the refill date on the canister, and on your calendar.

If you use your inhaler for rescue medicine, you probably won't be using it regularly enough for this method to work. In that case, ask your doctor if he or she will write a prescription for two inhalers at a time. Then get your prescription filled when the first inhaler is empty. This way, you'll always have enough rescue medicine on hand when you need it most.

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For more information talk to your doctor.


Written by editorial staff.

American Academy of Family Physicians

Reviewed/Updated: 08/06
Created: 01/92