Syringe assembly for lyophilizing, reconstituting and injecting a medication.

A syringe assembly includes a substantially cylindrical syringe barrel and a plunger assembly. The plunger assembly includes a distally disposed flow channelizer and a proximally disposed stopper releasably engaged with one another. The stopper includes an aperture engageable with the distal end of a plunger rod. The flow channelizer includes flutes for accommodating an outflow of vapor during lyophilization and to enable efficient mixing of a lyophilized medication and a diluent. Liquid medication in the syringe chamber is lyophilized and a vacuum is applied to the syringe barrel. The plunger assembly then is urged distally into sealing engagement with the syringe barrel. A plunger rod is engaged with the stopper, and is moved proximally to simultaneously separate the stopper from the flow channelizer and to draw diluent into the chamber for reconstituting the previously lyophilized medication.