A metered dose inhaler (MDI) is a handheld device filled with medicine that must be breathed into the lungs (inhaled). The medicine is delivered by pushing down on a metal canister. This releases a preset amount of spray and mist through the mouth and into the lungs. Each MDI canister holds a certain number of doses (puffs).

Using a spacer with a metered dose inhaler may be recommended to help get more medicine into the lungs. A spacer is a plastic tube that connects to the MDI on one end and has a mouthpiece on the other end. A spacer holds the medicine in the tube for a short time. This allows more medicine to be inhaled.

• Quick relief or rescue medicines, such as bronchodilators.
• Controller medicines, such as corticosteroids.

What are the risks?

• If you do not use your inhaler correctly, medicine might not reach your lungs to help you breathe.
• If you do not have enough strength to push down the canister to make it spray, ask your health care provider for ways to help.
• The medicine in the MDI may cause side effects, such as:
  • Mouth sores (thrush).
  • Cough.
  • Hoarseness.
  • Shakiness.
  • Headache.

Supplies needed:

• A metered dose inhaler.
• A spacer, if recommended.

How to use a metered dose inhaler without a spacer

1. Remove the cap from the inhaler.
2. If you are using the inhaler for the first time, shake it for 5 seconds, turn it away from your face, then release 4 puffs into the air. This is called priming.
3. Shake the inhaler for 5 seconds.
4. Position the inhaler so the top of the canister faces up.
5. Put your index finger on the top of the medicine canister. Support the bottom of the inhaler with your thumb.
6. Breathe out normally and as completely as possible, away from the inhaler.
7. Either place the inhaler between your teeth and close your lips tightly around the mouthpiece, or hold the inhaler 1–2 inches (2.5–5 cm) away from your open mouth. Keep your tongue down out of the way. If you are unsure which technique to use, ask your health care provider.
8. Press the canister down with your index finger to release the medicine. Inhale deeply and slowly through your mouth until your lungs are completely filled. Do not breathe in through your nose. Inhaling should take 4–6 seconds.
9. Hold the medicine in your lungs for 5–10 seconds (10 seconds is best). This helps the medicine get into the small airways of your lungs.
10. Remove the inhaler from your mouth, turn your head, and breathe out normally.
11. Wait about 1 minute between puffs or as directed. Then repeat steps 3–10 until you have taken the number of puffs that your health care provider directed.
12. Put the cap on the inhaler.
13. If you are using a steroid inhaler, rinse your mouth with water, gargle, and spit out the water. Do not swallow the water.

How to use a metered dose inhaler with a spacer

1. Remove the cap from the inhaler.
2. If you are using the inhaler for the first time, shake it for 5 seconds, turn it away from your face, then release 4 puffs into the air. This is called priming.
3. Shake the inhaler for 5 seconds.
4. Place the open end of the spacer onto the inhaler mouthpiece.
5. Position the inhaler so the top of the canister faces up and the spacer mouthpiece faces you.
6. Put your index finger on the top of the medicine canister. Support the bottom of the inhaler and the spacer with your thumb.
7. Breathe out normally and as completely as possible, away from the spacer.
8. Place the spacer between your teeth and close your lips tightly around it. Keep your tongue down out of the way.
9. Press the canister down with your index finger to release the medicine, then inhale deeply and slowly through your mouth until your lungs are completely filled. Do not breathe in through your nose. Inhaling should take 4–6 seconds.
10. Hold the medicine in your lungs for 5–10 seconds (10 seconds is best). This helps the medicine get into the small airways of your lungs.
11. Remove the spacer from your mouth, turn your head, and breathe out normally.
12. Wait about 1 minute between puffs or as directed. Then repeat steps 3–11 until you have taken the number of puffs that your health care provider directed.
13. Remove the spacer from the inhaler and put the cap on the inhaler.
14. If you are using a steroid inhaler, rinse your mouth with water, gargle, and spit out the water. Do not swallow the water.

Follow these instructions at home:

Caring for your MDI

• Store your inhaler at or near room temperature. A cold MDI will not work properly.
• Follow directions on the package insert for care and cleaning of your MDI and spacer.

General instructions

• Take your inhaled medicine only as told by your health care provider. Do not use the inhaler more than directed by your health care provider.
• Refill your MDI with medicine before all the preset doses have been used.
  • If your inhaler has a counter, check it to determine how full your MDI is. The number you see tells you how many doses are left.
  • If your inhaler does not have a counter, ask your health care provider when you will need to refill it. Then write the refill date on a calendar or on your MDI canister.
  • Keep in mind that you cannot tell when the medicine in an inhaler is empty by shaking it. You may feel or hear something in the canister even when the preset medicine doses have been used up. Keeping track of your dosages is important.
• Do not use any products that contain nicotine or tobacco, such as cigarettes, e-cigarettes, and chewing tobacco. If you need help quitting, ask your health care provider.
• Keep all follow-up visits as told by your health care provider. This is important.

Where to find more information

• Centers for Disease Control and Prevention: www.cdc.gov
• American Lung Association: www.lung.org

Contact a health care provider if:

• Symptoms are only partially relieved with your inhaler.
• You are having trouble using your inhaler.
• You have side effects from the medicine.
• You have chills or a fever.
• You have night sweats.
• There is blood in your thick saliva (phlegm).

Get help right away if:

• You have dizziness.
• You have a fast heart rate.
• You have severe shortness of breath.
• You have difficulty breathing.

These symptoms may represent a serious problem that is an emergency. Do not wait to see if the symptoms will go away. Get medical help right away. Call your local emergency services (911 in the U.S.). Do not drive yourself to the hospital.

Summary

• A metered dose inhaler is a handheld device for taking medicine that must be breathed into the lungs (inhaled).
• Take your inhaled medicine only as told by your health care provider. Do not use the inhaler more than directed by your health care provider.
• You cannot tell when the medicine is gone in an inhaler by shaking it. Refill it with medicine before all the preset doses have been used.
• Follow directions on the package insert for care and cleaning of your MDI and spacer.