A system for sequentially dispensing a non-user settable dose of one medicament followed by a user-settable dose of a primary medicament. The system may include a medicated module (202) attachable to a drug delivery device, the drug delivery device having a drug reservoir holding a first medicament. The medicated module includes a first needle (206), second needle (208), and a retention feature (212) fixed within a body of the medicated module. The module includes a recess (214) within the body of the medicated module and a piston (210) is slidably engaged with the recess. The module further includes a second medicament located in a first cavity (224) in the recess, where the first cavity is defined by a distal end of the piston and a distal end of the recess. The module also includes a diverter feature (228) that allows sequential delivery of the second medicament followed by the primary medicament.
