A metered-dose inhaler (MDI) is a handheld device that delivers a measured dose of medication directly to your lungs. The medication is usually in an aerosol form.

Using a spacer with an MDI is the most efficient way to get the most medication to your lungs. A spacer functions as a "holding" area for the medication before you inhale. Using a spacer with your MDI can improve the delivery of the medication and help you if you have problems with releasing the medication as you inhale. It might help to practice using the MDI and spacer in front of the mirror. A spacer should always be used with inhaled corticosteroids to avoid side effects.

An MDI can be used to give different types of medication. The type of medication in your inhaler will depend on what type of medication you need to treat your specific condition. For example, the inhaler may contain a medication to prevent an asthma attack or medication to help relieve the symptoms of COPD.

A medication may use a specific type of MDI. Always check with your health professional and pharmacist when getting a new MDI.

Using a metered-dose inhaler (MDI) is beneficial because:

• It provides a puff of medication in an accurate, measured dose.
• It can help keep your symptoms under control and may help prevent long-term damage to your lungs.
• When an MDI is used effectively, most of the medication is delivered directly to your lungs and does not travel throughout the body. This may prevent or decrease side effects in the rest of your body.
• You may be able to use less medication than is found in a pill but get the same effect.
• The medication may work faster than a pill.

To get started using your metered-dose inhaler (MDI):

1. Talk with your health professional 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 health professional has prescribed.
2. Check that you have the correct medication. 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 medication is in the inhaler. Check the label of your inhaler medication 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 medication is left. Your health professional 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 corticosteroids.

Using a spacer with an MDI is the most efficient way to get the most medication to your lungs. View a slideshow on the correct way to use an MDI with a spacer.

Although using an MDI with a spacer is usually recommended, you can also use an MDI without a spacer. View a slideshow on the correct way to use an MDI without a spacer.

If you are using a corticosteroid inhaler, rinse your mouth out with water after use. Do not swallow the water. Swallowing the water will increase the chance that the medication will get into your bloodstream. This may increase the side effects of the medication.

Some powder may build up on the inhaler, but it is not necessary to clean the inhaler every day. Occasionally rinse the spacer or mouthpiece, cap, and case.

Now that you have read this information, you are ready to start using a metered-dose inhaler.

Talk with your doctor

If you have questions about this information, take it with you when you visit your health professional.