The invention is directed to a dispense mechanism for a drug delivery device (1) for the delivery of a primary medicament (6) in a primary cartridge (5) and a secondary medicament (8) in a secondary cartridge (7). A primary drive member (14) and a secondary drive member (21) serve for driving a primary and a secondary lead screw, wherein the primary drive member (14) and the secondary drive member (21) are configured to rotate during dose dispense. A coupling member (17) serves for rotationally coupling the primary drive member (14) to the secondary drive member (21) and moves from a first position in which the primary drive member (14) is rotationally decoupled from the secondary drive member (21) into a second position in which the primary drive member (14) is rotationally coupled to the secondary drive member (21) during dose dispense. Rotation of the primary drive member (14) moves the coupling member (21) from the first position into the second position. The invention is also directed to a drug delivery device with a respective dispense mechanism. (Figure 1)Linvention concerne un mécanisme de distribution destiné à un dispositif (1) dadministration de médicament pour ladministration dun médicament principal (6) dans une cartouche principale (5) et dun médicament auxiliaire (8) dans une cartouche auxiliaire (7). Un élément dentraînement principal (14) et un élément dentraînement auxiliaire (21) servent à entraîner une vis-mère principale et une vis-mère auxiliaire, lélément dentraînement principal (14) et lentraînement dentraînement auxiliaire (21) étant conçus pour tourner pendant la distribution de dose. Un élément de raccordement (17) sert à raccorder en rotation lélément dentraînement principal (14) à lélément dentraînement auxiliaire (21) et passe dune première position dans laquelle lélément dentraînement principal (14) nest pas raccordé en rotation à lélément dentraînement auxiliaire (21) à une seconde position dans laquelle lélément dentraînement princip
