Opioids and Public Health: The Prescription Opioid Ecosystem and Need for Improved Management

Evan D. Kharasch, M.D., Ph.D.; J. David Clark, M.D., Ph.D.; Jerome M. Adams, M.D., M.P.H.


Anesthesiology. 2022;136(1):10-30. 

In This Article

The Opioid Pool

A foundational element of the opioid crisis is the size of the unused opioid pool available for potential diversion, misuse, addiction, and overdose. The pool is fed by the overprescription of oral opioids, including the aforementioned inappropriate outpatient use of oral opioids for acute and chronic noncancer pain. Many patients have leftover unused opioid pills, regardless of the indication for which they were prescribed. For example, a survey of more than 1,000 U.S. adults with recent opioid use reported that 57% had or expected to have leftover pills, and 49% planned to keep them for future use.[58]

Also contributory is the overprescription of oral take-home opioids after surgery, a problem reviewed previously in this journal,[59] and repeatedly documented further thereafter.[47,50,52,60–66] Surgeons prescribe approximately 10% of all opioids (and another 6% by dentists), and while this pales in comparison to the 33% prescribed by family practitioners and internists, surgical prescribing accounts for millions of patients and tens of millions of unused pills left over each year.[67] For example, among nearly 2,400 patients and 12 surgical procedures, a median of 30 postsurgical take-home opioid pills was prescribed per patient, and 19 pills were left over unused.[47] A recent large meta-analysis of 44 studies involving 13,068 patients found that an average 61% (95% CI, 56 to 67%) of postoperative opioids were leftover, equivalent to 582,000 5 mg hydrocodone tablets prescribed, and 355,000 tablets left over, or 27 tablets left over per person.[65]

Most patients do not return or dispose of unused prescription opioids, and do not store them in locked or inaccessible locations.[49,58,62,63,68–70] Leftover opioids may be used to self-medicate for indications other than those for which they were prescribed, voluntarily diverted to others for pain relief or other use, illegally diverted by theft, or accidentally ingested by toddlers, with consequent risks of misuse, abuse, addiction, and overdose.

Children and adolescents comprise a vulnerable population affected by the size and availability of the opioid pool.[71] Adolescent opioid misuse may lead to dependence, opioid use disorders, heroin use, and overdose.[71,72] In 2019, approximately 670 adolescents (12 to 17 yr) and 1,100 young adults (18 to 25 yr), compared with 2,625 adults (26 yr and older) initiated prescription opioid misuse each day.[38] Opioid-related pediatric hospitalizations doubled from 2004 to 2015.[73] One third were less than 6 yr old, suggesting accidental ingestion, and two thirds were 12 to 17 yr, suggesting deliberate misuse.[73] Adolescents freely divert prescription opioids.[71] The source of prescription opioids misused by adolescents (12 to 17 yr) differs from the population as a whole, and diversion is even more important than in adults. Misused opioids are obtained by diversion (from a friend or relative for free, purchase, or theft) more by adolescents (58%) than adults (51%) and less from prescription by adolescents (28%) than adults (37%.).[38,71] Opioids are found in more than one third of adolescents' homes, and many parents and caregivers are unaware of the risk they pose.[74] It is clear that current efforts to decrease adult opioid use have not diminished opioid exposure to children.[66,73,75]

The combination of outpatient opioid overprescribing, large amounts of unused opioids, retention for future use, and storage in unsecured accessible locations creates a vast risk space of hundreds of millions of opioid pills,[76] and opportunity for potential harm. This constitutes the opioid pool.