Evaluate the effect of IV line labels on nurses' identification of high-alert medications in a simulated scenario of multiple infusions for critically ill patients. Randomised crossover simulation experimental study. A study was conducted on 29 nurses working in intensive care for over 6 months. They were given two critical scenarios in a simulated environment, one with labels and the other without labels, involving multiple intravenous infusions. The nurses had to identify the medications infused into the critical patients' intravenous lines and disconnect a specific line. The data were collected and analysed to evaluate the errors made by the nurses in identifying and disconnecting the medications and the time they spent carrying out the tasks. The Wilcoxon test was used to analyse the variation in outcome before and after the intervention. Approximately one-third of the study participants incorrectly identified the intravenous lines in both scenarios. There was no significant difference in the average number of errors between the scenarios with and without labels. However, the time taken to perform the tasks in the scenario with labels was 1 min less than in the scenario without labels, suggesting a potential efficiency gain. The labels on the intravenous lines allowed for quick drug identification and disconnection. The professionals performed similarly in correctly recognising the high-alert medication intravenous lines, in the scenarios with or without labels. The label can be used as a technology to prevent misidentification of high-alert medications administered to critically ill patients through intravenous lines, thereby enhancing medication safety in healthcare institutions. No Public Contribution.