The sources of pharmaceuticals for problematic users of benzodiazepines and prescription opioids

There are growing concerns in Australia and overseas about the increasing misuse of a range of pharmaceuticals, and associated harms.1-4 This includes the problematic use of benzodiazepines and prescription opioids in Australia.

Clients of drug treatment services are commonly reported to use a range of pharmaceuticals.5-7 For example, self-reported prevalence of benzodiazepine use among clients undergoing treatment for opioid use ranges from 66% to 100%,5,7,8 and use confirmed by urine drug testing ranges from 51% to 70%.8 Moreover, benzodiazepine use is associated with poorer treatment and health outcomes among opioid users.9,10 In North America, prescription opioid-dependent clients outnumber heroin-dependent clients among those presenting for methadone maintenance treatment.6,11 Given the considerable harms that have been linked to these pharmaceuticals, including overdose12 and mortality,13,14 understanding their use and sources is important for informing effective harm-reduction interventions.

To our knowledge, no studies examining the sources of pharmaceuticals used by problematic users in Australia have been published, but sources of prescription opioids have been described in the United States. Among recent methadone treatment entrants who reported prescription opioids as the primary problem drug, the most common sources were dealers (86%), friends and relatives (54%) and medical prescriptions (28%).6 In contrast, the US National Survey on Drug Use and Health found most non-medical users sourced analgesics from a friend or relative for free (55%) or for payment (11%).15 In both studies, the internet was rarely a cited source.6,15

The Australian Government recently announced the introduction of a real-time reporting system for prescription opioids that doctors can use to obtain an up-to-date prescription history before prescribing drugs of addiction to any patient.16 It is planned that the reporting system will monitor Schedule 8 (S8) medications, therefore it will only include benzodiazepines that are S8. One benzodiazepine, flunitrazepam, is currently S8. Alprazolam will be rescheduled to S8 in 2014. To gauge the potential usefulness of such a system, it is important to understand how often these medications are being sourced through medical practitioners.

We describe (i) the characteristics of pharmaceutical use by Australian clients of drug treatment services who reported regular and unsanctioned use of benzodiazepines and/or prescription opioids and (ii) the common sources of benzodiazepines and prescription opioids used by these clients.

Detailed methods are available elsewhere.17 In brief, we recruited a convenience sample of 305 people entering treatment at private and public withdrawal (detoxification), residential rehabilitation and opioid substitution treatment services in Victoria, Western Australia, Queensland and Tasmania. They were recruited between January and July 2008 by referral from treatment service staff and using study flyers that were distributed from drug treatment services by the staff.

Treatment entrants were eligible to participate in the study if they: reported regular (an average of ≥ 4 days per week) and unsanctioned use of benzodiazepines and/or prescription opioids over the 4 weeks before treatment entry; were 16 years or older; had entered treatment for drug or alcohol use in the previous 6 months; and had sufficient English language skills to provide informed consent and comprehend the study questions. Unsanctioned use was defined as using medication that was not prescribed to the participant or using medication that was prescribed to the participant but in a way not intended by the prescriber (eg, taking a higher dose than prescribed, or injecting a drug that was intended as oral medication).

Structured face-to-face interviews of participants were conducted. They included questions on demographics (sex, age, ethnicity, employment, education level attained, current living arrangements), substance use (primary drug of concern at treatment entry, use in the 4 weeks before treatment entry, routes of administration), trajectories of substance use, and benzodiazepine and prescription opioid sources).

We used χ2 and t tests to establish whether there were differences between participants who used benzodiazepines and those who used prescription opioids. Descriptive analyses were used to characterise benzodiazepine and prescription opioid initiation, use and sources.

The study was approved by institutional ethics committees in each jurisdiction — the Victorian Department of Human Services Human Research Ethics Committee, University of Tasmania Social Sciences Human Research Ethics Committee, Curtin University Human Research Ethics Committee and Prince Charles Hospital Human Research Ethics Committee.

Our results provide information on how benzodiazepines and prescription opioids are accessed and used by people who represent the more “severe” end of the spectrum of problematic pharmaceutical drug users — drug and alcohol treatment entrants reporting almost daily use of benzodiazepines or prescription opioids.

We found that pharmaceutical use was initiated early (at an average of about 20 years of age), and about three-quarters of participants reported that their initial use was via a non-medical source. On average, it took 3–6 years for participants to progress from first use to regular or problematic use, suggesting that there is a window of opportunity for providing interventions that could avert this progression.

There were clear differences between how the two drug classes were sourced. Prescription opioids were less commonly acquired from a doctor than benzodiazepines, and most prescription opioids were acquired from non-medical sources. This is consistent with previously reported source patterns for prescription opioids.6,15 This common finding of sharing and onselling of prescription opioids has important implications for the medical profession. It highlights that while some individuals use opioids that were prescribed for other people, there may also be patients who do not use the opioids that are prescribed for them by their doctors. Most regular prescription opioid users reported buying their opioids from others, highlighting that this prescription drug black market is an important area to better understand. Also, prescription opioids were more likely to be injected than benzodiazepines.

In contrast to prescription opioids, a medical practitioner was the main source of benzodiazepines. As such, there may be considerable opportunities for prescriber intervention to address benzodiazepine use. This finding, coupled with the serious harms associated with benzodiazepines (in terms of acute overdose, poorer health and poorer treatment outcomes9,10,12,13), is interesting in light of current plans to only monitor the prescribing of S8 benzodiazepines as part of the monitoring of all S8 class drugs in Australia — flunitrazepam and, from 2014, alprazolam.16 This means that, despite the greater opportunity for prescribers to intervene in benzodiazepine supply, most benzodiazepines will not fall under the current plans for prescription drug monitoring. This also represents a missed opportunity for monitoring the impact of the planned rescheduling of alprazolam on the extent of use of other, unmonitored, benzodiazepines.

In contrast, monitoring opioid prescribing is unlikely to have a substantial impact on the behaviour of prescription opioid users, as they mostly acquire prescription opioids from non-medical sources. Also, it might give prescribers false confidence if they relied on the information from monitoring systems for the clinical assessment of drug-seeking behaviour alone, as opioids acquired from non-medical sources would not appear in such systems.

Other strategies — such as education of consumers and health professionals, and expansion of non-pharmaceutical evidence-based treatments for chronic pain and mental health disorders — are crucial. Approaches such as “universal precautions” with opioid prescribing have been recommended internationally18 and in Australian policy,19 but are yet to be established in practice.

Education for consumers on the harms associated with sharing medications is vital. Benzodiazepines are commonly implicated in non-fatal12 and fatal13,20 opioid overdose. We found that one-third of participants were given benzodiazepines as a gift for their most recent unsanctioned use. On first-use occasions, only one-quarter of benzodiazepines and prescription opioids were from a prescriber. Education about risks associated with self-diagnosis, peer diagnosis and self-medicating may help reduce medication sharing. Also, education initiatives for consumers could be used to challenge the perception that benzodiazepines are “less risky”21 than illicit drugs.

Our study has strengths and weaknesses. Convenience sampling and collection of self-reported data are well recognised and valid methods for studying individuals who engage in unsanctioned substance use22,23 and provide reliable answers in this context.23 However, it is well recognised that these methods affect the accuracy and representativeness of the data collected, compared with prospectively collected and objectively validated data from random or more generalisable samples.

The participants of our study had similar demographic characteristics to participants in other studies of drug treatment clients in Australia conducted in Australia.7,24 Although they may not represent most long-term problematic users of pharmaceuticals in the broader community, they represent a group who are more likely to experience acute harms from their pharmaceutical use and who use larger amounts of pharmaceuticals. As such, they are a priority when targeting strategies aimed at minimising pharmaceutical misuse.

These findings show that different approaches may be required to reduce unsanctioned use of different pharmaceuticals. Prescription drug monitoring programs need to ensure that the right substances are monitored. Current proposals may represent a significant lost opportunity with regard to the most benzodiazepines. Finally, developing guidelines and resources that help health professionals respond to pharmaceutical misuse identified through monitoring systems will maximise opportunities to reduce harm.