A computerized electro-mechanical drug delivery device configured to deliver at least one dose of two or more medicaments. The device comprises a control unit (300). An electro-mechanical drive unit (500,600) is operably coupled to the control unit and a primary reservoir (90) for a first medicament and a secondary reservoir (100) for a second medicament. An operator interface (60) is in communication with the control unit (300). A single dispense assembly (200) is configured for fluid communication with the primary (90) and the secondary (100) reservoir. Activation of the operator panel sets a first dose from the primary reservoir and based on the first dose, the control unit (300) is configured to determine a dose or range of the second medicament. Alternatively, the control unit determines or calculates a dose or range of a third medicament. Further, a dispense interface for use with a drug delivery device is disclosed.
