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A device attached to a metered-dose inhaler that aids delivery of inhaled medications.
Etymology: L, spatium, space
on a metered dose inhaler, a chamber between the inhaler canister and the patient's mouth where droplets of medication can slow down and evaporate so that there is less direct impact on the oropharynx, with more medication delivered to the lower respiratory tract instead of being lost in the mouth. This is especially helpful for children. See also metered dose inhaler.
An extension device for a metered-dose inhaler; it is designed to eliminate the need for hand-breath coordination and to reduce the deposition of large aerosol particles in the upper airway.
A specially shaped container that improves the delivery of inhaled aerosols, such as beta2 agonists, steroids, and other antiasthmatic drugs, to the bronchi and lungs. Spacers form a channel between metered dose inhalers and the mouth through which medicated mists can be inhaled. They improve the performance of antiasthmatic drugs because without them, a large quantity of inhaled medications end up in the mouth, on the palate, on the buccal mucosa, or on the tongue and fail to reach their intended target in the lower airways.
Spacers improve the delivery of inhaled drugs to any patient who cannot coordinate the use of metered dose inhalers, and in all patients who used inhaled steroids. They are also recommended for young children, e.g. under the age of 6.