A discharger comprising a housing, a piston arranged inside the housing and being movable between a first piston position and a second piston position, a hollow cylindrical container inside the housing, the container being movable between a first container position and a second container position, a first compartment defined within the housing, a second compartment defined within the container, an axially extending passage in the interior of the piston and in communication with the first compartment and a peripheral opening of the piston in the region of a proximal end of the piston, a sealing element configured to prevent communication between the second compartment and the peripheral opening of the piston when the container is in a first container position, and a releasable retaining device configured to retain the piston in a piston first position until the container has reached a second container position.