Introduction: Emergency medicine by its nature requires shift-work that often follows an erratic and unpredictable pattern. Faced with this ongoing challenge we hypothesized that many ED physicians may have taken steps to minimize their personal sleep deprivation through the use of a pharmacological sleep aid (PSA). The extent and nature of PSA use in this population is not well studied. We sought to describe the use of PSAs amongst practicing ED physicians in a Canadian tertiary-care setting. We also hoped to determine the specific substances being used, their frequency and predictive factors contributing to their use. Methods: A cross-sectional descriptive web-based survey was sent via e-mail to all practicing staff emergency physicians within the Calgary zone of Alberta Health Services. Participation was entirely voluntary and all responses were anonymous. Descriptive statistics were used to assess frequencies and summary measures. Logistic regression was used to explore associations between key variables. Results: Of the 198 eligible ED physicians, 144 (73%) completed the survey. 132 (92%) felt that shift-work negatively affected their ability to sleep and 121(84%) had experienced insomnia at some point in their medical career. 96(67%) ED physicians had used a PSA at some time in their career and 82(57%) were currently using a PSA with any frequency. The most frequent sleep aids currently being used were non-benzodiazepine hypnotics (65%), alcohol (31%) and melatonin (27%). 66(46%) respondents required a prescription for their PSA and 37(56%) of those had obtained a prescription from an ED physician colleague. Physician self-reporting of experience with insomnia was strongly associated with prior use of any PSA (OR 4.0; 95% CI 1.6-10.0) and prior use of non-benzodiazepine hypnotics (OR 14.4; 95% CI 3.2-64.2) There was no statistically significant association between current use of a PSA and physician age, physician gender, number of night shifts worked per month or co-habitation with children. None of the physicians who responded felt that their use of a PSA adversely affected their ability to provide quality patient care. Conclusion: Pharmacological sleep aid use among Canadian ED physicians may be more common than previously assumed. This could have implications for physician wellbeing and performance.