A drug delivery device comprising a main body extending between distal and proximal ends comprising a hollow cylinder comprising an outer and an inner surface, wherein the inner surface comprises threads a screw within the main body, comprising a hollow cylinder comprising an inner and an outer surface, wherein said outer surface comprises threads, wherein threads of outer surface of the screw are engaged with threads of inner surface of the main body a plunger extending between distal and proximal ends, wherein the distal end of the plunger engages the proximal end of the screw and a drug container extending between distal and proximal ends, and comprising a change in cross section from proximal to distal end, wherein the container is within the screw, and wherein the proximal end of the drug container is fixed to the screw and distal end of the container is fixed to the main body.
