This refers to a mechanism (2) to a device (1) of Drug Administration, which has a longitudinal AXIS (21) comprising a First Member (17) comprising a First Contact Surface (27) and a Second Member (18) including a Second Contact Surface To (29), where the first Member (17) is configured to be mounted to the second Member (18),Where the first Member and the second Member (17) (18) are configured so that the First Contact Surface (27) with the Second Top surface contact (29) when the first Member (17) is Mounted with the second Member (18),Where the First Contact Surface (27) is so arranged that a Force applied to the mechanism (2) in a direction parallel to the longitudinal AXIS (21) is divided into a First Component (30) in a direction perpendicular to a normal (28) to the surface of the first Surface Contact (27) and a Second Component (31) parallel to the Normal to the surface (28)Where the first Member and the second Member (17) (18) are configured so that the first Member (17) is separated from the second Member (18) by the Force applied to the mechanism (2) in a direction parallel to the longitudinal AXIS (21) if the Absolute value of the force is greater than a First Default valueAnd where the first Predetermined value is defined as the Absolute value of the force that has a First Component (30) large enough to displace the First Contact Surface (27) which does not stop with the second Member (18).La presente se refiere a un mecanismo (2) para un dispositivo (1) de administración de fármacos, que tiene un eje longitudinal (21) y que comprende un primer miembro (17) que comprende una primera superficie de contacto (27) y un segundo miembro (18) que comprende una segunda superficie de contacto (29), en donde el primer miembro (17) está configurado para ser montado con el segundo miembro (18), en donde el primer miembro (17) y el segundo miembro (18) están configurados de modo que la primera superficie de contacto (27) hace tope con la segunda superficie de conta
