Side effects from opioids used for acute pain after emergency department discharge

Am J Emerg Med. 2020 Apr;38(4):695-701. doi: 10.1016/j.ajem.2019.06.001. Epub 2019 Jun 3.


Objective: Opioid side effects are common when treating chronic pain. However, the frequency of opioid side effects has rarely been examined in acute pain conditions, particularly in a post emergency department (ED) setting. The objective of this study was to evaluate the short-term incidence of opioid-induced side effects (constipation, nausea/vomiting, dizziness, drowsiness, sweating, and weakness) in patients discharged from the ED with an opioid prescription.

Methods: This is a prospective cohort study of patients aged ≥18 years who visited the ED for an acute pain condition (≤2 weeks) and were discharged with an opioid prescription. Patients completed a 14-day diary assessing daily pain medication use and side effects.

Results: We recruited 386 patients with a median age of 54 years (IQR:43-66); 50% were women. During the 2-week follow-up, 80% of patients consumed opioids. Among the patients who used opioids, 79% (95%CI:75-83) reported side effects compared to 38% (95%CI:27-49) for non-users. Adjusting for age, sex, and pain condition, patients who used opioids were more likely to report constipation (OR:7.5; 95%CI:3.1-17.9), nausea/vomiting (OR:4.1; 95%CI:1.8-9.5), dizziness (OR:5.4; 95%CI: 2.2-13.2), drowsiness (OR:4.6; 95%CI:2.5-8.7), and weakness (OR:4.2; 95%CI:1.6-11.0) compared to non-users. A dose-response trend was observed for constipation but not for the other side effects. Nausea/vomiting (OR:2.0; 95%CI:1.1-3.6) and dizziness (OR:1.9; 95%CI:1.1-3.4) were more often associated with oxycodone than with morphine.

Conclusion: As observed for chronic pain treatment, side effects are highly prevalent during short-term opioid treatment for acute pain. Physicians should inform patients about those side effects and should consider prescribing laxatives.

Trial registration: NCT02799004.

Keywords: Acute pain; Constipation; Emergency department; Opioids; Side effect.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Analgesics, Opioid / adverse effects*
  • Analgesics, Opioid / therapeutic use
  • Cohort Studies
  • Drug-Related Side Effects and Adverse Reactions / epidemiology
  • Drug-Related Side Effects and Adverse Reactions / etiology*
  • Emergency Service, Hospital / organization & administration
  • Emergency Service, Hospital / statistics & numerical data
  • Female
  • Humans
  • Male
  • Middle Aged
  • Morphine / adverse effects
  • Morphine / therapeutic use
  • Oxycodone / adverse effects
  • Oxycodone / therapeutic use
  • Pain / drug therapy*
  • Pain Management / methods
  • Pain Measurement / methods
  • Patient Discharge / standards
  • Prospective Studies


  • Analgesics, Opioid
  • Morphine
  • Oxycodone

Associated data