The invention relates to an injection device (1) for the simultaneous administration of several medications. The injection device (1) comprises a carrying housing (5), an activation sleeve (8) surrounding the carrying housing (5), at least two carpules (9,11), a first drive module (13) for the administration of the medications, a securing device (14), a needle arrangement (17), a needle protection element (20), and a second triggerable drive module (21) for the needle arrangement (17). The carpules (9, 11) are arranged next to another. The first drive module (13) comprises a drive element (22) with a number of piston rods (23, 24) equal to the number of carpules (9, 11), which form a composite structural unit. At least one of the piston rods (23, 24) is configured in the form of a hollow cylinder and is formed as closed on the piston side, wherein arranged inside this is a first drive means (26) of the first drive module (13).
