BACKGROUND: Ketorolac tromethamine is a non-steroidal anti-inflammatory drug (NSAIDs) that is widely used in the emergency department (ED) for the treatment of moderate-to-severe pain. Ketorolac, like other NSAIDs, exhibits an analgesic ceiling effect and previous research suggests that 10 mg is possibly the ceiling dose. Do the patterns of ketorolac dosing by emergency physicians follow its analgesic ceiling dose? METHODS: This was a single center retrospective, descriptive study to characterize patterns of ketorolac administration in ED patients. Data for all patients who received ketorolac during the ten year study period from January 1, 2003 to January 1, 2013 were collected from the electronic medical record of an urban community ED with an annual volume of 116935 patients. RESULTS: There were 49605 ketorolac administrations during the study period; 38687 (78%) were given intravenously, 9916 (20%) intramuscularly, and 1002 (2%) orally. Through the intravenous route, 5288 (13.7%) were 15 mg, 32715 (84.6%) were 30 mg, 15 (0.03%) were 60 mg, and 669 (1.7%) were other varying doses. Through the intramuscular route, 102 (1.0%) were 15 mg, 4916 (49.6%) were 30 mg, 4553 (45.9%) were 60 mg, and 345 (3.5%) were other varying doses. The most common diagnoses at discharge were renal colic (21%), low back pain (17%) and abdominal pain (11%). CONCLUSION: The data show that ketorolac was prescribed above its ceiling dose of 10 mg in 97% of patients who received intravenous doses and in 96% of patients receiving intramuscular doses.