"Among patients who are prescribed opioids, an estimated 80% are prescribed low doses (<100 mg morphine equivalent dose per day) by a single practitioner (7,8), and these patients account for an estimated 20% of all prescription drug overdoses (Figure 3). Another 10% of patients are prescribed high doses (?100 mg morphine equivalent dose per day) of opioids by single prescribers and account for an estimated 40% of prescription opioid overdoses (9,10). The remaining 10% of patients are of greatest concern. These are patients who seek care from multiple doctors and are prescribed high daily doses, and account for another 40% of opioid overdoses (11). Persons in this third group not only are at high risk for overdose themselves but are likely diverting or providing drugs to others who are using them without prescriptions. In fact, 76% of nonmedical users report getting drugs that had been prescribed to someone else, and only 20% report that they acquired the drug from their own doctor (4). Furthermore, among persons who died of opioid overdoses, a significant proportion did not have a prescription in their records for the opioid that killed them; in West Virginia, Utah, and Ohio, 25%–66% of those who died of pharmaceutical overdoses used opioids originally prescribed to someone else (11–13). These data suggest that prevention of opioid overdose deaths should focus on strategies that target 1) high-dosage medical users and 2) persons who seek care from multiple doctors, receive high doses, and likely are involved in drug diversion."
Centers for Disease Control, CDC Grand Rounds: Prescription Drug Overdoses — a U.S. Epidemic, Morbidity and Mortality Weekly Report, January 13, 2012 / 61(01);10-13