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Metered Dose Inhalers for Asthma

What is a metered dose inhaler with an Aerochamber with mask?

Inhaled asthma medications are often delivered by using a device called a metered dose inhaler, or "MDI." The MDI is a small aerosol canister in a plastic holder that delivers a puff of medication to the lungs.

To help make it easier for your child to use the MDI and ensure the delivery of medication gets into the lungs, your child may use a spacer chamber (with or without a mask) with the MDI. The purpose of the spacer chamber is to hold the medication released from the MDI so that your child has the time to more effectively inhale the medication. The contents of an MDI are under pressure and are released quickly, making it difficult to coordinate inhalation of the particles. The spacer chamber suspends these particles until your child breathes in, reducing the amount of coordination required to inhale the particles, thus easing the delivery of medication into the lungs. Adults should also use a spacer chamber, especially if they have problems using the MDI. Spacer chambers can also reduce the deposition of particles in your mouth or tongue and therefore may reduce side effects from medications. Spacer chambers should not be used with a dry powder inhaler (DPI).

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How Does my Child Use a Metered Dose Inhaler With a Spacer Chamber and Mask?

Directions for using the metered dose inhaler with a spacer chamber (and mask) are given below. Read these instructions before using the device. Your asthma care team will also teach you and your child how to use these devices.

To use the MDI and spacer (with or without a mask):

  1. Remove the caps from the MDI and spacer chamber.
  2. Shake the canister well.
  3. Insert the MDI into the back end of the spacer chamber.
  4. If there is a mask, place it over your child's nose and mouth, making sure there is a good seal. If there is just a mouth piece, the tip should go between the teeth and lips wrapped tightly around to make a good seal.
  5. Press down firmly on the canister to release one puff of the medication into the spacer chamber.
  6. Hold the mask firmly in place while your child takes at least six breaths. If your child is using a spacer chamber with mouth piece, after inhaling the medication, he should hold his breath for 5-10 seconds then breathe out slowly.
  7. Wait one minute.
  8. Repeat steps two through seven for each puff of medication ordered.
  9. When treatment is complete, remove the MDI from the space chamber.
  10. If using this device with an MDI that contains a steroid, wipe your child's face with soap and water after use to remove any medication. If possible, also rinse your child's mouth with water.


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