A device is disclosed for dispensing a fluid supplied from an external
fluid source. The device comprises a transducer adapted to receive a
fluid from the fluid source, and a collapsible linkage coupling the
transducer and the fluid source. The linkage has a collapsible joint
inhibiting discharge of the fluid source when in a locked orientation.
The device further comprises a movable member coupled to the linkage such
that inhalation forces on the device cause the linkage to collapse
thereby discharging the fluid from the fluid source. The device may
further include a dose counter coupled to the fluid source for
registering the amount of doses administered from the fluid source.