Metered dose inhalation unit with slide means

摘要

A spray-entrapped product such as dispensed by an MDI device includes an elongated passageway having a mouthpiece portion and a main chamber portion. The MDI device is mounted to direct a medication spray into the main chamber. A first air inlet allows a low-level inspiratory breath to be developed through the unit prior to operation of the MDI device. When the MDI device is operated a second, air inlet is opened, allowing a higher-level breath to be developed, which causes a high level of mixing with the MDI spray for efficient draws into the lungs. The second air inlet remains open after MDI operation ceases, insuring that a complete, high flow rate breath can be made to fully sweep the medication out of the chamber.