The present invention relates to a drive mechanism for a drug delivery device, comprising a number of mechanically interacting functional components among which at least a piston rod is adapted to transfer thrust to a piston of a cartridge that contains a medicinal product to be dispensed, wherein at least one of the functional components at least in sections comprises a friction-reducing slide coating. In this way, a force level required for dispensing and/or setting of a dose can be effectively reduced.
