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Breathing Problems: Using a Metered-Dose Inhaler


Diseases affecting the lungs—such as asthma, emphysema, chronic bronchitis, and chronic obstructive pulmonary disease (COPD)—share many of the same medicines. These medicines are often delivered through a metered-dose inhaler (MDI).

Using an MDI:

  • Delivers most of a measured dose of medicine directly to your lungs.
  • Can help keep your symptoms under control and minimize long-term damage to your lungs.
  • May prevent or reduce side effects of the medicine.
  • May let you use less medicine than is found in a pill but get the same effect.
  • May result in the medicine working faster than a pill form.

How to use a metered-dose inhaler

Getting started

  1. Talk with your doctor to be sure that you are using your MDI correctly. It might help if you practice using it in front of a mirror. Use the inhaler exactly as your doctor has prescribed.
  2. Check that you have the correct medicine. If you use several inhalers, put a label on each one so that you know which one to use at the right time.
  3. Check how much medicine is in the inhaler. Check the label of your inhaler medicine to see how many inhalations should be in the canister. If you know how many breaths you can take, you can replace your inhaler before you run out. Learn how to test your canister to estimate how much medicine is left. Your doctor or pharmacist can help you with this.
  4. Use a spacer if you have problems getting the correct timing when you use an inhaler or if you are using corticosteroid medicine.

Using an MDI

Using a spacer with an MDI is the most efficient way to get the most medicine to your lungs. Make sure you understand the proper use of:

Although using an MDI with a spacer is usually recommended, you can also use an MDI without a spacer. Learn the proper use of:

If you are inhaling steroid medicine, rinse your mouth out with water after use. Do not swallow the water. Swallowing the water will increase the chance that the medicine will get into your bloodstream. This may increase the side effects of the medicine.

Some liquid may build up on the inhaler, but you may not need to clean the inhaler every day. Follow the directions for how and how often to clean the type of MDI you have.


Current as of:
July 6, 2021

Author: Healthwise Staff
Medical Review:
E. Gregory Thompson MD - Internal Medicine
Brian D. O'Brien MD - Internal Medicine
Adam Husney MD - Family Medicine
Ken Y. Yoneda MD - Pulmonology
Martin J. Gabica MD - Family Medicine