A nebulizer for a fluid, includes a container containing the fluid; a housing part which can be detached from the nebulizer for replacing the container; an inner part; a retaining element connected with and not detachable from the inner part, where the housing part is releasable fixed to the inner part by the retaining element; a delivery mechanism for dispensing the fluid; a manually depressible actuator member, which is a separate part from the retaining element and acts on the retaining element, and wherein the actuator member is depressed to elastically deform or flex the retaining element to allow detachment of the housing part.