A multi chamber syringe unit (1) comprises a body (2), a separating element (3) and a bypass arrangement (26). The body (2) has a distal end side (23), a proximal end side (22) opposite to the distal end side (23), an interior limited by a side wall (21) between the distal end side (23) and the proximal end side (22) and a longitudinal axis (27) centrally extending from the distal end side (23) to the proximal end side (22) through the body. The separating element (3) is arranged in the interior of the body (2) forming a distal chamber (24) between the distal end side (23) and the separating element (3) and a proximal chamber (25) between the proximal end side (22) and the separating element (3). The bypass arrangement (26; 260; 268; 269) is a section of the body (2) in which the interior has a constant noncircular cross section (261) orthogonal to the longitudinal axis (27). The multi camber syringe unit (1) allows for being efficiently prepared and for efficiently providing or administering high quality of prefilled products.