Intentional and Unintentional Prescription Opioid Exposures in Italy, Australia, Germany and the United States

Introduction: Prescription Opioid abuse in the United States (US) has been called epidemic. US Rates of abuse are high and rising. However, abuse and/or misuse in other countries is not well studied. This study provides abuse rate data for three common opioids over a five year period from 2007 to 2011 in Italy, Australia, the United States and Northwest Germany.

Methods: Human exposures to oxycodone, buprenorphine, and methadone reported from 2007-2011 were obtained from the Milan, Australia and Göttingen Poison Centers. Data from the US were obtained from Poison Centers participating in the RADARS® System. Poison Centers in all four countries manage calls from healthcare providers and the public. The Milan poison center handles 65-70% of all Poison center calls in Italy. Rates are expressed as the number of exposures per 100,000 population separately for intentional and unintentional exposures. Intentional exposures are those with a reason of suicide, abuse, misuse, and unknown intentional. Unintentional exposures consist of those exposures with a reason of unintentional general, unsupervised ingestions or therapeutic errors.

Results: In Italy, rates of intentional exposures to oxycodone changed 615%, methadone -3% and buprenorphine -65% from 2007 to 2011. Unintentional exposure rates increased 249% for oxycodone, 11% for methadone and by 59% for buprenorphine from 2007 to 2011. In Australia intentional and unintentional exposure rates for oxycodone are highest.  Oxycodone intentional exposure rates increased   86% over this 5 year period; oxycodone unintentional exposure rates increased 177% over this 5 year period. In Northwest Germany rates of intentional exposure to oxycodone increased 90%, methadone 40% and buprenorphine 31% from 2007 to 2011. Unintentional exposure rates for oxycodone increased 475%, methadone 40% and buprenorphine 0%. In the US 2011 intentional exposures rates to oxycodone were 34%, methadone -7% and buprenorphine 103% changed from 2007 to 2011.  US unintentional exposures rates to oxycodone were 14%, methadone -21%, and buprenorphine 115% changed from 2007 rates.

Conclusions: Rising rates of opioid exposures are not unique to the U.S. and may be on the verge of becoming a global challenge. Tracking exposure trends with international poison center data may enable other nations to employ proactive prevention strategies to address the abuse of prescription opioids and avoid the epidemic currently facing the United States.