Both opioid and non-opioid analgesics are commonly utilized in treating acute and chronic pain in the emergency department (ED). Opioid stewardship efforts have focused on judicious opioid use and opioid alternatives as first-line analgesics. Parenteral opioid formulations have been impacted by periodic shortages creating the opportunity for a natural experiment to observe how emergency clinician prescribing behavior may be impacted. We investigated the change in analgesic practice related to a period of parenteral opioid shortage at two large urban, academic medical centers. A retrospective review of pharmacy administration data from two academic urban EDs was performed looking at time periods before, during, and after resolution of the parenteral opioid shortage. The data were analyzed by medication, dose, time, number of doses, and oral morphine milligram equivalents (MME) administered per patient. The percentage of patients who received any opioid among ED visits decreased during the shortage period and did not return to pre-shortage levels after the shortage ended: 11.5% pre, 8.5% during (p=0.01), 7.2% post (NS; p=0.18). The number of doses of either oral or IV opioid doses administered during the shortage decreased significantly: 8.7% pre, 5.6% during (p=0.02) for PO, and 13.7% pre, 9.0% during (p=0.004) for IV, and neither changed during recovery from the shortage. The percentage of patients receiving non-opioid analgesics rose from 30.5% before to 45.8% (p=0.004) after the shortage. Among patients who received opioids, the MME per patient did not change across the time periods: 11.5% before, 11.2% during, 12.7% post. A period of restricted opioid use due to parenteral opioid shortages led to less opioid use overall and fewer patients treated with opioids, yet no significant change in opioid MME administered per patient requiring opioids. Overall, the shift in opioid prescribing during the parenteral opioid shortage appeared to be sustained in the post-shortage period.