A drug delivery device (1) is provided comprising a housing (4), a lead screw (22) that is rotatably fixed with respect to the housing (4) during dose setting and during dose delivery and that is axially moveable in a delivery direction relative to the housing (4) for dose delivery, a number sleeve (23) threadedly engaged with the housing (4) to be screwable relative to the housing (4), and a dial link (25a) which is axially moveable and rotatable with respect to the housing (4) for dose setting and which is prevented from rotation with respect to the housing (4) for dose delivery. The dial link (25) is rotatably fixed with the number sleeve (23) when the dial link (25a) and the number sleeve (24) are in a first arrangement, and the number sleeve (24) and the dial link (25a) are rotatable with respect to one another when the dial link (25) and the number sleeve (24) are in a second arrangement. The device (1) further comprises a unidirectional coupling (100) which is adapted and arranged to allow a relative rotation between the dial link (25a) and the number sleeve (24) in a first direction while preventing relative rotation between the dial link (25a) and the number sleeve (24) in a direction opposite to the first direction when the dial link (25a) and the number sleeve (24) are in the second arrangement.La présente invention concerne un dispositif de distribution de médicament (1) comprenant un boîtier (4), une vis-mère (22) qui est fixée de façon rotative par rapport au boîtier (4) pendant le réglage de dose et pendant la distribution de dose et qui est axialement déplaçable dans une direction de distribution par rapport au boîtier (4) pour la distribution de dose, un manchon numérique (23) associé par filetage avec le boîtier (4) de manière à pouvoir être vissé par rapport au boîtier (4), et une liaison de cadran (25a) qui est axialement déplaçable et rotative par rapport au boîtier (4) pour le réglage de dose et qui est empêchée de tourner par rapport au boîtie