How do people co-use Benzodiazepines and opioids throughout the day: a qualitative study

Background

The co-use of benzodiazepines or Z-drugs (BZ) and opioids (OP) has been linked to the 2-3 fold rise in drug related deaths (DRD) and risk of death experienced by people who use OP in Scotland. Previously reported patterns of co-use vary from using BZs prior to, after or at the same time as OP depending on the motivation for use. However, more detail is needed (e.g. timing between doses of BZ and OP) to inform future harm reduction strategies, and reduce DRD. This study explored how people co-use BZ and OP, their preferred combinations, dosages, timings, methods of administration and desired effects. 

Methods 
Forty-eight semi-structured interviews across Bristol (n=10), Teesside (n=10) and Glasgow (n=28) with individuals who co-use illicit/prescribed OP and BZ were conducted. Eighteen interviews were co-facilitated with qualitatively trained local peer researchers to support in-depth exploration of how people co-use. Interviews were recorded, anonymised, transcribed and analysed using the Framework method.  

Results  
Five overarching temporal co-use patterns were generated: (1) Low-dose BZ: prescribed/illicit BZ (≤40mg BZ /≤75mg zopiclone) split into a morning and evening dose. Morning dosages were co-used with prescribed OP to manage anxiety, sleep, and withdrawals with heroin and cocaine consumed between these doses. (2) Coming down with street BZs: prescribed OP in the morning, stimulants throughout the day, followed by a low evening dose (≤30mg) of street BZs. (3) Co-use throughout: a daily co-use pattern which involved frequent redosing of both BZ and opioids (leading to a high total dose), with other polydrug use aiming to achieve euphoria and/or escape reality. (4) BZ binges: were finance and availability driven, triggered by trauma or a potent batch. Not a daily pattern and involved high doses of BZ, leading to reduced inhibitions, memory loss and unintended co-use of OP and further BZ doses. (5) Curated co-use: participants described carefully varying timing, doses, combinations or choosing different BZs to achieve specific mood states.  
 
Most reported a preference for one pattern but some interchanged between two. Often their patterns changed at different points of their life, with co-use throughout the day/BZ binges relating to periods of heavier drug use. People reporting BZ binges and co-use throughout the day were more likely to have experienced intentional and unintentional (non-fatal) overdose(s). No distinctions were found between individuals co-using BZ versus Z-drugs, or preference for the order of consumption between BZs and opioids. Further, no differences in patterns were found according to sex, geographic location, those with prescribed BZ or OP.
 
Conclusions 
These patterns are currently informing neuropharmacological studies into how combinations of BZ and OP lead to fatal overdose – which in combination with our qualitative studies will inform harm reduction advice to reduce drug related harm and DRD.