An actuation mechanism 10 for an automatic injector 100 includes a first actuation spring 102, a first actuation pill 104, a second actuation spring 106, and a second actuation pill 108. In an initial configuration the first actuation spring 102 resides in a compressed, energized state substantially within an upper portion of first actuation pill 104 and the second actuation spring 106 resides in a compressed, energized state between the first actuation pill 104 and the second actuation pill 108. An automatic injector 100 includes a housing 14, 16, an activation mechanism 12, an actuation mechanism 10, and a syringe cartridge 20 having a plunger 200 and a needle assembly 40. A retractable syringe may be utilized as a syringe cartridge 20, such as a prefilled retractable syringe with integrated safety features which retract the needle 420 after use. The automatic injector 100 may be utilized to inject the needle 420, deliver a drug treatment, and activate retraction of the needle 420. Methods of assembly and operation are also provided.
