An auto-injector pen has an outer housing (12, 14) which has a proximal end (18) and a distal end (16), an inner housing (84) having a cartridge (74) therein, the cartridge (74) containing a medicament and having one end thereof sealed by pierceable member (80), a needle hub (64) having first and second piercing tips (68, 70) which are in fluid communication, an actuating assembly (28) which moves an actuator from a first position to an activated position wherein the first piercing tip (68) extends outwardly of the outer housing (12,14) at the proximal end (18) and the second piercing tip (70) pierces the pierceable member (80), a first trigger (22) located at the distal end (16) and a second trigger (98) located at proximal end 18, the arrangement being such that the second trigger 98 must be activated to permit activation of the first trigger (22).