OBJECTIVE We analysed the rate of physical restraint in acute and chronic psychiatric patients and looked at the safety of waiving venous thromboembolic disease (VTE) prophylaxis in the case of restraining of less than 24 h. METHODS We did a retrospective analysis of all episodes of restraining in 2012 and 2013, diagnosis of restrained patients, time of restraining and use of low molecular weight heparin (LMWH) for prophylaxis of VTE associated with restraining. RESULTS Overall, 12 734 patients were hospitalised. The number of episodes of restraining was 1035 and involved 469 (7.4%) patients. Only 79 episodes of restraining lasted more than 24 h and affected only 36 (0.3%) individual patients. The most frequent psychiatric diagnoses were unstable borderline personality in 41 (52%) and schizophrenic or schizoaffective psychosis in 26 (33%) episodes. None of these prolonged restraints and none of the 956 episodes of restraining for less than 24 h were associated with clinical symptoms or signs of VTE that would have required additional diagnostic consequences. CONCLUSION The concept of waiving VTE prophylaxis within the first 24 h of restraining seems to be safe. On the other hand, LMWH sufficiently protected the small sample being restrained for more than 24 h.