A collapsible inhaler for use with a metered dose inhaler (MDI) dispenser that is operable to dispense a metered dose of medicament therefrom, the inhaler comprising: an inlet member being adapted to receive an MDI dispenser and having an inlet therein; an outlet member comprising an outlet therein, a conduit which is pliable and has a distal end associated with the inlet member and a proximal end associated with the outlet member, a support associated with the pliable conduit that is adjustable between an expanded state and a contracted state whereby in the contracted state the inlet member is positioned proximate the outlet member, while in the expanded state the support supports the pliable conduit and combined with the inlet member being spaced from the outlet member that defines a chamber, so that in use a metered dose of medicament can be dispensed from the MDI dispenser through the inlet in the inlet member to mix with air in the chamber and be inhaled by a patient through the outlet in the outlet member, wherein the inhaler further comprises a lockout mechanism for inhibiting operation of the MDI dispenser when the support and conduit are in the contracted state and not inhibiting operation of the MDI dispenser when the support and conduit are in the expanded state.L'invention concerne un inhalateur pliable pour utilisation avec un aérosol-doseur qui peut fonctionner pour distribuer une dose calibrée de médicament, l'inhalateur comprenant : un élément d'entrée conçu pour recevoir un aérosol-doseur et comportant un orifice d'entrée ; un élément de sortie comprenant un orifice de sortie, un conduit qui est pliable et comporte une extrémité distale associée à l'élément d'entrée et une extrémité proximale associée à l'élément de sortie, un support associé au conduit pliable qui est réglable entre un état déployé et un état replié, moyennant quoi, à l'état replié, l'élément d'entrée est positionné à proximité de l'élément de sortie, tandis qu'à l'état déployé, le