An assembly for mixing drug components includes a housing to at least partially hold a first drug component container and a second drug component container. The assembly also includes a transfer member having first and second ends to fluidly couple the respective first and second drug component containers. The assembly further includes a pressure member to fluidly couple the first drug component container to a pressure generation chamber. In addition, the assembly includes an energy storage member to generate pressure in the pressure generation chamber to transfer a fluid from the first drug component container into the second drug component container. Moreover, the assembly includes an exit member to fluidly couple the second drug component container to an exterior of the assembly.
