Poison Center Program Research Articles

Changes in Hydrocodone Misuse Exposures Reported to U.S. Poison Centers Following Rescheduling in 2014

Background In 2014, the Drug Enforcement Administration rescheduled hydrocodone combination products to Schedule II to reduce nonmedical use and diversion. Methods The impact of rescheduling was assessed using quarterly data from 2011 through 2019 from the Researched Abuse, Diversion and Addiction-Related Surveillance (RADARS®) System Poison Center Program and IQVIATM Longitudinal Prescription Data. Trends and immediate changes in prescriptions dispensed and misuse exposures before and after rescheduling involving hydrocodone, oxycodone, and other Schedule II opioid analgesics were calculated using segmented regression. Results Hydrocodone prescriptions were stable pre-rescheduling, decreased by 2.7% (95% CI: −3.6%, −1.8%, p < 0.0001) per quarter post-rescheduling. Misuse exposures involving hydrocodone were decreasing by 3.2% (95% CI: −3.9%, −2.4%, p < 0.0001) per quarter pre-rescheduling and decreased by 4.9% (95% CI: −5.5%, −4.2%, p < 0.0001) post-rescheduling. Immediate decreases in hydrocodone prescriptions and misuse exposure rates in 2014Q4 compared to 2014Q3 were significant and different from oxycodone or other Schedule II opioids. Schedule II opioid analgesics prescriptions in aggregate were stable prior to rescheduling, decreased by 10.8% (95%CI: −14.0%, −7.6%, p < 0.0001) immediately after the rescheduling, and decreased by 2.3% per quarter (95% CI: −3.1%, −1.5%, p < 0.0001) subsequently. Misuse exposures involving these opioids were decreasing by 3.3% (95% CI: −4.1%, −2.5%, p < 0.0001) prior to rescheduling then by 2.8%, (95% CI: −3.4%, −2.2%, p < 0.0001) after rescheduling. The immediate change in misuse was not significant. Conclusions Rescheduling corresponded with changes in hydrocodone prescribing and misuse not offset by increases in other Schedule II opioid analgesics. Misuse exposures for hydrocodone and comparators were decreasing prior to rescheduling with little change post-intervention.

The impact of the prescription opioid epidemic on young children: Trends and mortality

BackgroundOur objective was to describe trends and deaths in young children associated with opioid analgesics. MethodsAnalysis of pediatric exposures using the RADARS System Poison Center Program from July 1, 2010 through December 31, 2018. Cases involving a child < 6 years, with an exposure to one or more opioids: buprenorphine, fentanyl, hydrocodone, hydromorphone, methadone, morphine, oxycodone, oxymorphone, and tramadol. Poisson regression was used to model the shape of the time response curve. Results48,560 cases were identified, median age 2 years (IQR 1.4, 2.0), 52.4 % male. The most commonly involved opioid was hydrocodone (32.5 %); buprenorphine and methadone had the highest exposure rates when adjusted for dispensed prescriptions (0.84 and 0.73 per 10,000 prescriptions). There were 28 deaths, methadone being the most commonly involved opioid (16). Exposures decreased significantly accounting for population (from 8.39 to 4.19 exposures per 100,000 children) and per prescription (from 0.33 to 0.25 exposures per 10,000 prescriptions). After adjustment for prescriptions, the exposure rate for hydromorphone and fentanyl increased over the study period, while buprenorphine had the greatest decrease in exposure rate. Among 28 deaths, 11 (39 %) were known or suspected to have been exposed, but medical care was not sought or was delayed. ConclusionPediatric opioid exposure rates by prescription and population decreased from July 2010 through December 2018. However, with over 48,000 exposures and 28 deaths, the opioid epidemic continues to impact young children. Many exposures including deaths were preventable. Continued improvements in prevention require a multifaceted approach.

Consistency Between Opioid-Related Mortality Trends Derived From Poison Center and National Vital Statistics System, United States, 2006-2016.

To determine the association between poison center opioid exposure calls and National Vital Statistics System (NVSS) deaths. We categorized Centers for Disease Control and Prevention NVSS mortality and the Researched Abuse, Diversion and Addiction-Related Surveillance System poison center program cases from 2006 to 2016 by International Classification of Diseases, Tenth Revision, codes (heroin [T40.1]; natural or semisynthetic opioids [T40.2]; methadone [T40.3]; synthetic opioids, other than methadone [T40.4]). We scaled rates by 100 000 population and calculated Pearson correlation coefficients. Sensitivity analysis excluded polysubstance cases involving either heroin or synthetic opioids as well as natural and semisynthetic opioids. The NVSS mortality and poison center program exposure rates showed similar trends from 2006 to 2012, and diverged after 2012 for all opioids combined, natural and semisynthetic opioids, and synthetic opioids (r = -0.37, -0.12, and 0.30, respectively). Sensitivity analysis with removal of heroin or synthetic opioid polysubstance deaths markedly improved correlations for all opioids combined and natural and semisynthetic opioids (r = 0.87 and 0.36, respectively). The NVSS mortality and poison center exposure rates showed similar trends from 2006 to 2012 then diverged, with sensitivity analysis suggesting polysubstance cases also involving heroin or illicit fentanyl as the cause. Public Health Implications. The NVSS and poison center program may provide complementary data when trends diverge. Public health interventions must include both licit and illicit opioids for maximal impact.

Unit-Dose Packaging and Unintentional Buprenorphine-Naloxone Exposures.

Buprenorphine accounts for the most opioid-related pediatric hospital admissions when compared with other opioid analgesics. Since 2010, several manufacturers began distributing their buprenorphine products with unit-dose packaging (UDP). Our main objective in this study is to evaluate the impact of UDP on unintentional pediatric buprenorphine-naloxone poison center exposures. This is an observational surveillance study in which the Researched Abuse, Diversion, and Addiction-Related Surveillance System Poison Center Program is used. The main outcome was cases of unintentional ingestions involving children <6 years old and buprenorphine-naloxone (combination) products. The study was split into 3 periods: pre-UDP (first quarter 2008 through fourth quarter 2010), transition to UDP (first quarter 2011 through fourth quarter 2012), and post-UDP (first quarter 2013 through fourth quarter 2016). Overall, there were 6217 exposures to combination products. In the pre-UDP period, there were 20.57 pediatric unintentional exposures per 100 000 prescriptions dispensed; in the transition to UDP period, there were 8.77 pediatric unintentional exposures per 100 000 prescriptions dispensed; and in the post-UDP period, there were 4.36 pediatric unintentional exposures per 100 000 prescriptions dispensed. This represents a 78.8% (95% confidence interval: 76.1%-81.3%; P < .001) relative decrease from the pre-UDP period. The shift from non-UDP to UDP in over 80% of buprenorphine-naloxone products was associated with a significant decrease in unintentional pediatric exposures reported to poison centers. Packaging controls should be a mainstay in the approach to the prevention of unintentional buprenorphine pediatric exposures as well as exposures to other prescription opioids.

Comparative Rates of Mortality and Serious Adverse Effects Among Commonly Prescribed Opioid Analgesics

The epidemic of prescription opioid overdose and mortality parallels the dispensing rates of prescription opioids, and the availability of increasingly potent opioid analgesics. The common assumption that more potent opioid analgesics are associated with higher rates of adverse outcomes has not been adequately substantiated. We compared the rate of serious adverse events among commonly prescribed opioid analgesics of varying potency. Serious adverse events (SAEs; defined as death, major medical effect, or hospitalization) resulting from exposure to tablets containing seven opioid analgesics (oxycodone, hydrocodone, morphine, hydromorphone, oxymorphone, tapentadol, and tramadol) captured by the Researched Abuse, Diversion and Addiction-Related Surveillance (RADARS®) System Poison Center Program were evaluated from 2010 through 2016. Rates of SAEs were adjusted for availability through outpatient dispensing data and regressed on morphine milligram equivalents (MME). There were 19,480 cases of SAE during the 7-year study period. Hydrocodone and oxycodone contributed to 77% of SAE cases. Comparing rates of outcome by relative potency, a hierarchy was observed with hydromorphone (8.02 SAEs/100kg) and tapentadol (0.27 SAE/100kg) as the highest and lowest rates, reflecting a 30-fold difference among individual opioid products. SAE rate and potency were related linearly-SAEs increased 2.04 per 100kg drug dispensed for each 1-unit rise in MME (p = 0.004). Linear regression of SAE/100kg drug dispensed and drug potency identified that MME comprised 96% of the variation observed. In contrast, potency did not explain variation seen using other study denominators (prescriptions dispensed, dosage units dispensed, and the number of individuals filling a prescription). Potency of a prescription opioid analgesic demonstrates a significant, highly positive linear relationship with exposures resulting in SAEs per 100kg drug dispensed reported to poison centers. Potency should be carefully considered from both individual provider and public health perspectives.

Understanding abuse of buprenorphine/naloxone film versus tablet products using data from ASI-MV® substance use disorder treatment centers and RADARS® System Poison Centers

ObjectivesThe objectives were to examine the abuse prevalence and route-of-administration (ROA) profiles of sublingual buprenorphine/naloxone combination (BNX) film in comparison with the BNX tablet and to identify clinically-relevant subgroups of patients or geographic patterns. MethodsBetween Q1 2015 through Q3 2015, data were collected from two major surveillance systems: (1) assessment of individuals in substance use disorder (SUD) treatment collected from the National Addictions Vigilance Intervention and Prevention Program (NAVIPPRO®) ASI-MV® system and (2) intentional abuse/misuse exposures in the RADARS® System Poison Center Program. Poisson regression models were tailored to each system's data characteristics by population (all SUD treatment patients, US census) and adjusted for prescription volume. Effects of gender, race, age and US region as well as ROA profile were examined. ResultsFor the ASI-MV study, 45,695 assessments of unique adults evaluated for substance use problems were collected. The abuse rate unadjusted for prescription volume of BNX tablet formulation was 2.64 cases/100 ASI-MV respondents versus 7.01 cases for the film formulation (RR=0.390, p<0.001). Prescription-adjusted abuse, however, was greater for the tablet version (0.47 abuse cases/100 ASI-MV respondents/100,000 dosage units compared with 0.38 for the film) (RR=1.25, p<0.001). Results among the US population from the RADARS System Poison Center Program data revealed a similar pattern; population rates for film abuse (0.0364) were greater than for tablet (0.0161), while prescription-adjusted rates were greater for tablet (0.2114) than for film (0.1703) per 100,000 prescriptions. ASI-MV ROA analyses indicated less abuse of the film by any alternate route, insufflation or injection than the tablet. Poison center data found more injection of tablets than film, although insufflation was not significantly different. ConclusionsOn a prescription-adjusted basis, overall abuse of the BNX tablet is greater than that of the sublingual film formulation. For those who continue to abuse BNX, use by alternate ROAs was, in general, lower for the film.

Changes in misuse and abuse of prescription opioids following implementation of Extended-Release and Long-Acting Opioid Analgesic Risk Evaluation and Mitigation Strategy.

An unintended consequence of extended-release (ER) and long-acting (LA) prescription opioids is that these formulations can be more attractive to abusers than immediate-release (IR) formulations. The US Food and Drug Administration recognized these risks and approved the ER/LA Opioid Analgesic Risk Evaluation and Mitigation Strategy (ER/LA REMS), which has a goal of reducing opioid misuse and abuse and their associated consequences. The primary objective of this analysis is to determine whether ER/LA REMS implementation was associated with decreased reports of misuse and abuse. Data from the Researched Abuse, Diversion and Addiction-Related Surveillance (RADARS(R)) System Poison Center Program were utilized. Poison center cases are assigned a reason for exposure, a medical outcome, and a level of health care received. Rates adjusted for population and drug utilization were analyzed over time. RADARS System Poison Center Program data indicate a notable decrease in ER/LA opioid rates of intentional abuse and misuse as well as major medical outcomes or hospitalizations following implementation of the ER/LA REMS. While similar decreases were observed for the IR prescription opioid group, the decreasing rate for the ER/LA opioids exceeded the decreasing rates for the IR prescription opioids and was distinctly different than that for the prescription stimulants, indicating that the ER/LA REMS program may have had an additional effect on decreases in opioid abuse and intentional misuse beyond secular trends.

Medical outcomes associated with prescription opioid abuse via oral and non-oral routes of administration

BackgroundPrescription opioid abuse and misuse is a serious and growing public health issue. While the most common form of abuse is swallowing intact tablets/capsules, some abusers manipulate, or tamper with, these medications by altering the dosage form to allow for non-oral routes of administration (e.g., injection, inhalation) in order to achieve more rapid or enhanced psychoactive effects. Because administration of opioids via non-oral routes results in greater systemic availability and more rapid central nervous system penetration, we hypothesized that death and major medical outcomes occur more frequently with non-oral routes compared to oral route alone. MethodsThis retrospective cohort study analyzed data from the Researched Abuse, Diversion and Addiction-Related Surveillance (RADARS) System Poison Center Program to investigate relative risk of prescription opioid abuse via oral and non-oral routes. ResultsWhile the oral route was the most commonly reported route of abuse (64.0%), non-oral routes were reported in 14.6% exposures and unknown routes in 21.4% exposures. The relative risk of an exposure resulting in death or major effect was 2.43 (95% CI 1.97, 2.99) if non-oral routes were reported compared to exposures involving oral route only. ConclusionAnalysis of acute health events recorded by poison centers indicates that death or major effects are twice as likely to occur with intentional abuse of prescription opioids via non-oral routes of administration than ingestion alone. Effective interventions to prevent abuse via non-oral routes of solid dosage forms of prescription opioids, such as abuse-deterrent formulations could have a significant public health impact.

Sustained reduction of diversion and abuse after introduction of an abuse deterrent formulation of extended release oxycodone

BackgroundThe development of abuse deterrent formulations is one strategy for reducing prescription opioid misuse and abuse. A putative abuse deterrent formulation of oxycodone extended release (OxyContin®) was introduced in 2010. Early reports demonstrated reduced abuse and diversion, however, an analysis of social media found 32 feasible methods to circumvent the abuse deterrent mechanism. We measured trends of diversion, abuse and street price of OxyContin to assess the durability of the initial reduction in abuse. MethodsData from the Poison Center Program, Drug Diversion Program, Opioid Treatment Program, Survey of Key Informant Patients Program and StreetRx program of the Researched Abuse, Diversion, and Addiction-Related Surveillance (RADARS®) System were used. The average quarterly rates of abuse and diversion for OxyContin were compared from before reformulation to the rate in second quarter 2015. Rates were adjusted for population using US Census data and drug availability. ResultsOxyContin abuse and diversion declined significantly each quarter after reformulation and persisted for 5 years. The rate of abuse of other opioid analgesics increased initially and then decreased, but to lesser extent than OxyContin. Abuse through both oral and non-oral routes of self-administration declined following the reformulation. The geometric mean difference in the street price of reformulated OxyContin was 36% lower than the reformulated product in the year after reformulation. DiscussionDespite methods to circumvent the abuse deterrent mechanism, abuse and diversion of OxyContin decreased promptly following the introduction of a crush- and solubility- resistant formulation and continued to decrease over the subsequent 5 years.

(144) Routes of administration of tapentadol products as reported to poison centers

Tapentadol immediate-release (NUCYNTA) was launched in June 2009 with the extended-release product (Nucynta® ER) released in August 2011. Tapentadol is a centrally-acting analgesic with μ-opioid receptor agonistic and norepinephrine reuptake inhibition activities. In an effort to deter abuse, particularly through unintended routes of administration, the extended-release tablets were manufactured using Intac® technology to be difficult to crush for intranasal abuse and difficult to solubilize for intravenous abuse. Cases classified in the Intentional Exposure category in the Poison Center Program of the Research Abuse, Diversion, and Addition-Related Surveillance (RADARS®) System were analyzed and used to test whether the proportion of cases reporting use via injection or inhalation is lower for extended-release tapentadol than for immediate release (IR) tapentadol. Between the launch of the extended-release product and June 2015, there were 303 Intentional Exposures involving ER tapentadol and 217 Intentional Exposures involving IR tapentadol. Of the 303 ER tapentadol intentional exposures, 178 (58.8%) were classified as Suspected Suicides and 47 (15.5%) were Intentional Abuse exposures. Of all ER tapentadol exposures, 5 (1.7%) of the 303 exposures reported use via injection or inhalation, all of which were Intentional Abuse exposures. Of the 217 IR tapentadol cases classified as Intentional Exposure, 55.8% were Suspected Suicide exposures and 14.3% were Intentional Abuse exposures. Ten (4.6%) of these exposures reported use via injection or inhalation. Of these, 8 were Intentional Abuse exposures, 1 was Suspected Suicide, and 1 was Intentional Misuse. The proportion of tapentadol ER exposures mentioning injection or inhalation use is significantly lower than the proportion of IR tapentadol exposures (χ2=3.95, p=0.047). Though intentional exposures still exist, extended-release tapentadol is associated with fewer incidents of injection or inhalation use in cases reported to the RADARS System poison centers. Supported by a research grant from Depomed, Inc.

Buprenorphine/naloxone pediatric ingestion: Exposure rates differ between film and tablet formulations

RADARS System Poison Center program case counts and medical outcomes for unintentional exposures to buprenorphine/naloxone tablets and oral film among children aged 0 – 5 years from October 2009 to March 2013 were analyzed. To account for drug availability, rates were standardized using unique recipients of a dispensed drug (URDD) per year-quarter. Negative binomial regression was used to estimate rates and confidence intervals. Average quarterly rates were calculated from 2011/Q2 – 2013/Q1. 1,695 reports of unintentional exposure to sublingual buprenorphine products were analyzed.

A new standardised MedDRA query to address drug abuse-related safety signals

A new standardised MedDRA query to address drug abuse-related safety signals

Assessment of prescription opioid intentional exposures across the rural-urban continuum in the United States using both population and drug availability rates.

Prescription opioid abuse and misuse are a serious problem in the U.S. today. Several studies have shown that the epidemic disproportionately affects rural areas. This paper uses three different rates to gain a more complete picture of opioid abuse in rural areas. This study examines prescription opioid intentional exposures using opioid classes tracked in the RADARS(®) System Poison Center Program. Intentional exposure rates were calculated adjusting for population and unique recipients of dispensed drug (URDD). These rates were analyzed using time (quarter) and the proportion of a three-digit zip code residing in a rural area as covariates. Additionally, the URDD per population rate was calculated to examine the proportion of the population filling prescriptions for opioids. After adjusting for population, intentional exposure cases significantly increased as the proportion of the population residing in a rural area increased. However, when adjusting for URDD, intentional exposure cases decreased with increasing rural population. The URDD per population increased as the proportion of people residing in a rural area increased. Using both population and URDD adjusted intentional exposure rates gives a more complete picture of opioid abuse in rural areas. Considering product availability can be used to develop opioid abuse prevention strategies and further the education of physicians serving rural areas about this epidemic.

(139) Reformulation of extended release oxymorphone: changes in intentional abuse exposures before and after introduction of tamper resistant formulation

Studies indicate that abuse of extended release (ER) oxymorphone tablets increased following reformulation of an ER oxycodone product (OxyContin®) in August 2010. In February 2012, Endo pharmaceuticals reformulated ER oxymorphone (Opana® ER) to be resistant to tampering. This analysis examines changes in Opana ER abuse rates following introduction of these formulations using intentional abuse exposure case mentions from the RADARS® System Poison Center Program. Rates per number of prescriptions filled were compared across three time periods: before reformulation of ER oxycodone and ER oxymorphone (2009Q3 to 2010Q2), after reformulation of ER oxycodone and before reformulation of ER oxymorphone (2011Q1 through 2011Q4), and after reformulation of both ER oxycodone and ER oxymorphone (2012Q3 to 2013Q2).

Abuse and diversion of buprenorphine sublingual tablets and film

Buprenorphine abuse is common worldwide. Rates of abuse and diversion of three sublingual buprenorphine formulations (single ingredient tablets; naloxone combination tablets and film) were compared. Data were obtained from the Researched Abuse, Diversion, and Addiction-Related Surveillance (RADARS®) System Poison Center, Drug Diversion, Opioid Treatment (OTP), Survey of Key Informants' Patients (SKIP), and College Survey Programs through December 2012. To control for drug availability, event ratios (rates) were calculated quarterly, based on the number of patients filling prescriptions for each formulation (“unique recipients of a dispensed drug,” URDD) and averaged and compared using negative binomial regression. Abuse rates in the OTP, SKIP, and College Survey Programs were greatest for single ingredient tablets, and abuse rates in the Poison Center Program and illicit diversion rates were greatest for the combination tablets. Combination film rates were significantly less than rates for either tablet formulation in all programs. No geographic pattern could be discerned.

Root Causes, Clinical Effects, and Outcomes of Unintentional Exposures to Buprenorphine by Young Children

To characterize the rates, root causes, and clinical effects of unintentional exposures to buprenorphine sublingual formulations among young children and to determine whether exposure characteristics differ between formulations. Unintentional exposures to buprenorphine-containing products among children 28 days to less than 6 years old were collected from the Researched Abuse, Diversion, and Addiction-Related Surveillance System Poison Center Program and Reckitt Benckiser Pharmaceuticals' pharmacovigilance system from October 2009-March 2012. After adjustment for drug availability, negative binomial regression was used to estimate average exposure rates. Root cause assessment was conducted, and an expert clinician panel adjudicated causality and severity of moderate to severe adverse events (AEs). A total of 2380 cases were reviewed, including 4 deaths. Exposures to buprenorphine-naloxone combination film were significantly less frequent than exposures to buprenorphine tablets (rate ratio 3.5 [95% CI, 2.7-4.5]) and buprenorphine-naloxone combination tablets (rate ratio 8.8 [7.2-10.6]). The most commonly identified root causes were medication stored in sight, accessed from a bag or purse, and not stored in the original packaging. Among 536 panel review cases, the most common AEs reported for all formulations were lethargy, respiratory depression, miosis, and vomiting. The highest level AE severity did not differ significantly by formulation. Unintentional exposure to buprenorphine can cause central nervous system depression, respiratory depression, and death in young children. Exposure rates to film formulations are significantly less than to tablet formulations. Package and storage deficiencies contribute to unintentional exposures in young children.

Surveillance of Diversion and Nonmedical Use of Extended-Release PrescriptionAmphetamine and Oral Methylphenidate in the United States

This article examines rates of nonmedical use and diversion of extended-release amphetamine and extended-release oral methylphenidate in the United States. Prescription dispensing data were sourced from retail pharmacies. Nonmedical use data were collected from the Researched Abuse, Diversion and Addiction-Related Surveillance (RADARS) System Drug Diversion Program and Poison Center Program. Drug diversion trends nearly overlapped for extended-release amphetamine and extended-release oral methylphenidate. Calls to poison centers were generally similar; however, calls regarding extended-release amphetamine trended slightly lower than those for extended-release oral methylphenidate. Data suggest similar diversion and poison center call rates for extended-release amphetamine and extended-release oral methylphenidate.

Poster 99 Difference in Rates of Abuse Following Reformulation of Extended Release Oxycodone Using Data from the Radars® System Poison Center Program

Poster 99 Difference in Rates of Abuse Following Reformulation of Extended Release Oxycodone Using Data from the Radars® System Poison Center Program

92 Difference in Rates of Abuse Following Reformulation of Extended Release Oxycodone Using Data From the RADARS® System Poison Center Program

Study Objectives: In August 2010, a reformulated version of OxyContin (oxycodone HCl controlled-release) tablets was introduced, which is intended to deter crushing and forms a gel when dissolved, with the goal of deterring abuse through routes that require tampering. This study examines whether there was a decline in rates of abuse and therapeutic errors of OxyContin reported to poison centers participating in the RADARS® System after introduction of reformulated OxyContin (ORF). Poison centers participating in the program covered 90% of the US population in the 3rd quarter of 2011.Methods: Mentions of OxyContin and other prescription products (“exposures”) were obtained on a quarterly basis from participating poison centers. Exposures were coded by reason, including intentional abuse and unintentional therapeutic errors. Therapeutic errors are defined as a deviation from a proper therapeutic regimen that results in the wrong dose, incorrect route of administration, administration to the wrong person, or administration of the wrong substance. Rates were calculated for abuse and for unintentional therapeutic error exposures per 100,000 population and per 1,000 unique recipients of dispensed drug (URDD) for each year/quarter. October 1, 2008 through September 30, 2010 was considered the period before and October 1, 2010 to December 31, 2011 was considered the period after introduction of ORF. These poison center data do not differentiate between exposures to original OxyContin versus ORF in the after period. The mean abuse rates for OxyContin as well as other prescription opioid drugs were compared before and after introduction of ORF using negative binomial regression.Results: There was a 34% (95% CI: 26-42%) decline in the average abuse rate of OxyContin per 100,000 population and 29% (95% CI: 20-36%) decline in the rate per 1,000 URDD after the introduction of ORF. The declines in the abuse rate for OxyContin were greater than changes observed for all other opioids (P<0.0001). There was a 22% (95% CI: 12-32%) decline in the rate of unintentional therapeutic error exposures of OxyContin per 100,000 population and a 16% (95% CI: 10-22%) decline per 1,000 URDD after introduction of ORF. The declines in the therapeutic error rate for OxyContin were greater than changes observed for all other opioids when measured per 100,000 population (p=0.0003), but not when measured per 1,000 URDD (p=0.098). Study Objectives: In August 2010, a reformulated version of OxyContin (oxycodone HCl controlled-release) tablets was introduced, which is intended to deter crushing and forms a gel when dissolved, with the goal of deterring abuse through routes that require tampering. This study examines whether there was a decline in rates of abuse and therapeutic errors of OxyContin reported to poison centers participating in the RADARS® System after introduction of reformulated OxyContin (ORF). Poison centers participating in the program covered 90% of the US population in the 3rd quarter of 2011. Methods: Mentions of OxyContin and other prescription products (“exposures”) were obtained on a quarterly basis from participating poison centers. Exposures were coded by reason, including intentional abuse and unintentional therapeutic errors. Therapeutic errors are defined as a deviation from a proper therapeutic regimen that results in the wrong dose, incorrect route of administration, administration to the wrong person, or administration of the wrong substance. Rates were calculated for abuse and for unintentional therapeutic error exposures per 100,000 population and per 1,000 unique recipients of dispensed drug (URDD) for each year/quarter. October 1, 2008 through September 30, 2010 was considered the period before and October 1, 2010 to December 31, 2011 was considered the period after introduction of ORF. These poison center data do not differentiate between exposures to original OxyContin versus ORF in the after period. The mean abuse rates for OxyContin as well as other prescription opioid drugs were compared before and after introduction of ORF using negative binomial regression. Results: There was a 34% (95% CI: 26-42%) decline in the average abuse rate of OxyContin per 100,000 population and 29% (95% CI: 20-36%) decline in the rate per 1,000 URDD after the introduction of ORF. The declines in the abuse rate for OxyContin were greater than changes observed for all other opioids (P<0.0001). There was a 22% (95% CI: 12-32%) decline in the rate of unintentional therapeutic error exposures of OxyContin per 100,000 population and a 16% (95% CI: 10-22%) decline per 1,000 URDD after introduction of ORF. The declines in the therapeutic error rate for OxyContin were greater than changes observed for all other opioids when measured per 100,000 population (p=0.0003), but not when measured per 1,000 URDD (p=0.098).