The medical bed has two longitudinal barriers, each formed of three or four bed rails made of hollow aluminium profile having an oblong cross-section. The rails are connected to one another through the straps (14) retained within the profiles of the rails through clips (not shown). At each end of each rail (6), a sliding shoe (11) protrudes from end segment (6a or 6c) of the rail and slides in the hollow profile of one of the C-shaped profile forming uprights located at both ends of the bed. The higher bed rail (6) has at each end a ratchet or retractable catch (8) that fits into a cut (13a) in the upper end of the C-shaped profile of the upright.
