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Asthma Health Center

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Metered Dose Inhalers for Asthma

What is a metered dose inhaler with a spacer ?

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. These devices are recommended for all children who have difficulty coordinating breathing and the use of the inhaler correctly (particularly children less than five to six years old).

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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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