The reformulation of OxyContin (oxycodone) into a supposedly abuse-deterrent formula (ADF) has reduced illicit use of the drug but has also caused people to switch to other opioid drugs, primarily heroin, a US study published in JAMA Psychiatry
on 11 March 2015 shows.
The ADF tablet also remains open to abuse, with many people continuing to use OxyContin by swallowing the tablets or by circumventing the “ADF” mechanisms in order to inject or snort the drug.
The findings are “a major concern”, says Theodore Cicero, study co-author, from Washington University, St Louis, Missouri. “Some people have come to see [heroin] as a cost-effective method of getting high,” he adds.
OxyContin, a prescription opioid painkiller dubbed “hillbilly heroin”, is a class A drug that is substantially stronger than morphine. It is highly addictive and has been linked to tens of thousands of deaths in the United States. In England, prescriptions for oxycodone increased by 39% between 2010 and 2014. There were more than one million NHS scripts for the drug in 2014.
In an attempt to curb epidemic levels of abuse, the manufacturer Purdue Pharma reformulated the drug in 2010. The ADF pill is difficult to crush and snort, and several studies have found that the move led to a rapid drop in illicit use of the drug.
In the new research, Cicero and his co-author explored how drug-seeking behaviour changed after the ADF pill was released. Structured surveys were completed by 10,784 patients with a DSM-V diagnosis of opioid use disorder and whose primary drug of abuse was a prescription opioid or heroin; additional in-depth interviews were conducted with a subset of patients.
After introduction of the ADF pill, the proportion of patients reporting having used OxyContin within the past month fell from 45.1% in 2009 to 26.0% in 2012, a figure that remained stable up to the end of 2014.
Interviews with 153 patients who had used the original OxyContin formulation revealed that 33.3% continued to abuse the ADF formulation, 33.3% replaced OxyContin with other drugs (heroin in 70% of cases), 3.3% had stopped abusing drugs altogether and the remaining 30.1% did not use OxyContin enough to change their choice of drug.
Among the patients who had used both pre-ADF and ADF formulations, 43% said they had transitioned from non-oral to oral routes of intake, 34% had managed to circumvent the “ADF” mechanisms and were still snorting or injecting the drug and 23% had only ever taken the drug orally and continued to do so.
“OxyContin is not currently as serious a problem [in the United Kingdom] as it is in the United States, however, misuse and diversion of opioid painkillers generally is a growing problem and one that needs to be addressed as a matter of urgency,” says Oscar D’Agnone, medical director of drug charity Crime Reduction Initiatives.
“This study raises again the importance of healthcare professionals working with clients to address the underlying causes of an addiction, and supporting them into long-term recovery, to reduce the possibility of one substance being substituted for another,” he adds.