A medicated module (4) for an injection system to co-deliver at least two medicaments (1, 2) is disclosed where a primary delivery device (7) contains a first drug agent and accepts a medicated module (4) containing a single dose of a secondary premix medicament (2) containing the first drug agent and at least a second drug agent, where both the primary medicament (1) and the secondary premix medicament (2) are delivered through a single hollow needle (3, 16, 21, 31).
