How do we manage the risks from street benzos?

By Catriona Matheson and Roy Robertson

In this piece we want to start to think about how we can manage and support people who are regularly using, and probably dependent on street benzodiazepines alongside opiates like heroin or methadone and possibly other drugs and alcohol.  There is a big drive from some to provide a ‘safer’ supply of benzodiazepines, in other words prescribing benzodiazepines so people are not at risk of unpredictable street supplies.  In this piece I will explore the issue of risk in more detail – but first – we want to remind us of the motivations for using street benzodiazepines.  People we have spoken to in the course of our research, describe taking street benzodiazepines for their sedative effect.  This might be to self-medicate for trauma, anxiety, sleep problems and pain.  So people who use street benzos regularly may have particular issues or characteristics that makes them different to those who do not use street benzos regularly.  This is important to bear in mind when we now consider what the research evidence tells us about the safety of prescribing a ‘safer’ supply of benzodiazepines for people who are also on opiate replacement treatment like methadone or buprenorphine.

There have now been a number of good quality studies on the effects of benzodiazepines from across the world that either studied a group of people in detail or used large datasets of prescription information.  We have also been conducting our own study in Scotland.  The evidence, from across the world strongly indicates that combining the prescription of an opioid with a benzodiazepine increases the risk of death from any cause when compared to prescription on an opioid and no benzodiazepine ^1-5.  There is also some evidence of increased risk of a drug related death more specifically when comparing an opioid with and opioid prescribed alongside a benzodiazepine.  An Australian study has also found a ‘substantial’ increase in risk of accidental overdose if prescribed an opioid with a benzodiazepine and a gabapentinoid!⁶  There is still a lack of evidence about the risks of  use of less familiar benzodiazepines and not enough information about the, often,  excessive quantities used. Our own Scottish data analysis found a smaller level of risk than that in studies from elsewhere (more on that when we have it published).  But – the same evidence generally also found, the beneficial effect, that people prescribed a benzodiazepine were less likely to leave treatment early.

In understanding what this means for prescribing we need to consider whether people being prescribed a benzodiazepine and/or a gabapentinoid are different from people not prescribed these drugs?  Might they have characteristics that make them more at risk?  Coming back to motivations for use of street benzos, the answer is very likely yes!  This is a higher risk group with more mental health, pain and sleep problems and therefore not directly comparable.  This is why a trial is needed in which there is no difference in the characteristics of the groups being compared. It may be that the risk of death attributed to benzodiazepines is complicated by other factors.

Thinking of the drugs alone (without the human aspect), it is not a surprise that prescribing two or more sedatives are associated with higher risk of overdose or death.  We have known this from general medicine for as long as there have been sedative products available.  It is why sedatives or central nervous system depressant medicines are labelled with this warning:

Warning: This medicine may make you sleepy. If this happens, do not drive or use tools or machines. Do not drink alcohol.

So what about relative risk?  There is risk in taking drugs/medicines that make you sleepy, affect your memory or affect your general ability to think. This risk exists whether prescribed or not.  However, with prescribed medication you at least know what drug and dose you are taking.  So we need to consider the balance of risks of street sourced drugs versus prescribed drugs.  There is risk for the person who uses street benzodiazepines, there is risk for the person prescribed an opiate and a benzodiazepine (and maybe other drugs like gabapentin or antidepressants) and there is risk for prescribers if they prescribe multiple sedatives that plays a part in causing death from overdose or accident. Current guidelines for prescribers understandably take the view that benzodiazepines are inherently likely to increase the risk of overdose or death and avoid the danger of being implicated in causing harm. This approach will, however, miss the opportunity to reduce the harm from a more toxic consequence from the unregulated and unknown content of illicit drugs and to draw vulnerable people into supportive services.

Prescribing a medication should never be the only treatment offered.  In the next article we will describe an intervention addressing the key motivating factors for benzodiazepine use.  By addressing reasons for taking street benzodiazepines we can reduce risk.

References

1. Abrahamsson T, Berge J, Öjehagen A, Håkansson A. Benzodiazepine, z-drug and pregabalin prescriptions and mortality among patients in opioid maintenance treatment-A nation-wide register-based open cohort study. Drug Alcohol Depend 2017;174:58-64.
2. Bakker A, Streel E. Benzodiazepine maintenance in opiate substitution treatment: Good or bad? A retrospective primary care case-note review. J Psychopharmacol 2017;31(1):62-66.
3. Macleod J, Steer C, Tilling K, Cornish R, Marsden J, Millar T, et al. Prescription of benzodiazepines, z-drugs, and gabapentinoids and mortality risk in people receiving opioid agonist treatment: Observational study based on the UK Clinical Practice Research Datalink and Office for National Statistics death records. PLoS Med 2019;16(11):e1002965.
4. Park TW, Larochelle MR, Saitz R, Wang N, Bernson D, Walley AY. Associations between prescribed benzodiazepines, overdose death and buprenorphine discontinuation among people receiving buprenorphine. Addiction 2020;115(5):924-932.
5. Sharma V, Simpson SH, Samanani S, Jess E, Eurich DT. Concurrent use of opioids and benzodiazepines/Z-drugs in Alberta, Canada and the risk of hospitalisation and death: A case cross-over study. BMJ Open 2020;10(11).
6. Bharat C, Gisev N, Barbieri S, Dobbins T, Larney S, Farrell M, Dagenhardt L. The Effects of opioid antagonists, benzodiazepines, gabapentinoids and opioid agonist treatment on mortality risk among opioid dependent people. NDARC, University of New South Wales. Poster presentation INHSU, Glasgow October 2022.