This invention concerns an ampoule nebulizer per aerosol therapy at different medicament delivery speeds. It comprises a body with a through conduit (30) for the delivery of ambient air from outside. The though conduit is associated with a selection push-button (31) which moves between a first blocking or partially blocking position of the entry of said conduit for the choice of a first low feed speed and at least a second opening position of the entry of said conduit in order to choose a second higher medicament feed speed. Said positions are defined by stop means (35, 36) and between one and the other, one or more additional intermediate positions can be provided. Furthermore, the selection push-button can be associated with an additional valve (132) in order to vary the flow of ambient air from outside during functioning at low speed.
