Patient Characteristics and Outcomes in Unintentional, Non-fatal Prescription Opioid Overdoses: A Systematic Review

Pain Physician. 2016 May;19(4):215-28.


Background: Opioid overdose continues to be a significant and growing cause of preventable mortality and morbidity. Studies suggest that unintentional, non-fatal overdose from prescription opioid analgesics constitutes a large portion of total overdose events. The societal burden associated with these events is a frequently overlooked public health concern.

Objectives: To evaluate unintentional, non-fatal prescription opioid overdoses, including the identification of risk factors, societal burden, and knowledge gaps where further study is warranted.

Study design: Systematic review of the literature for unintentional, non-fatal opioid overdose.

Methods: Preferred reporting items for systematic reviews and meta-analyses guidelines were used in constructing this systematic review. To determine the scope of the existing literature, a systematic search was conducted using the MEDLINE, CINAHL, PsycINFO, and Web of Science databases.

Results: This systematic review analyzes 24 articles (21 retrospective descriptive analyses, 2 prospective analyses, one phase III trial, and one meta-analysis). Articles were reviewed by authors and relevant data examined. Results show that opioid overdose morbidity is significantly more prevalent than mortality and sequelae of non-fatal events should be studied in more detail.

Limitations: The limitations of this systematic review include the range of study populations and opioids discussed and the broad and variable definitions of "opioid overdose" in the literature.

Conclusions: Opioid overdose morbidity and mortality is seen across the entire spectrum of inpatient and outpatient use with significant numbers of adverse events occurring in population segments not identified by high risk indicators. Increased physician awareness and a multi-modal approach could help mitigate the overdose epidemic while maintaining effective pain control for patients.

Key words: Prescription, opioid, accidental drug overdose, unintentional overdose, drug poisoning, fentanyl, oxycodone, hydrocodone, methadone, oxymorphone, hydromorphone.

Publication types

  • Review
  • Systematic Review

MeSH terms

  • Analgesics, Opioid / adverse effects*
  • Drug Overdose / epidemiology*
  • Drug Overdose / mortality
  • Humans
  • Prescription Drug Overuse / mortality
  • Prescription Drug Overuse / statistics & numerical data*


  • Analgesics, Opioid