Benzodiazepine use - current trends: evidence review

3. Considerations and concerns in treatment for problem benzodiazepine use

The data presented in this paper outline some of the key trends in benzodiazepine use in Scotland; the role of benzodiazepines in drug-related deaths; hospital stay rates, police seizures and prescribing practices. The data highlight the immense scale of benzodiazepine-related harms in Scotland and the challenges that exist in both tackling illicit supply and providing appropriate, evidence-based treatment for benzodiazepine use.

Benzodiazepine use among problem substance using populations has a longstanding history in Scotland, interwoven with complex polydrug use patterns. The approach to reducing harms and mortality related to benzodiazepines is not straightforward and existing clinical guidance on best approaches to harm reduction and treatment often remains conflicting. At present, there continues to be little consensus among experts and stakeholders on the safety, efficacy, benefits and harms of benzodiazepine prescribing as a treatment for substance dependency.^[48]

Current UK clinical guidelines on the treatment of substance dependency suggest minimising the long-term prescription of benzodiazepines, except in exceptional circumstances.^[49] Exceptional circumstances are given as previous long-term benzodiazepine prescriptions; clear evidence of relevant comorbid mental health problems; and clear 'deterioration' following previous benzodiazepine detoxification. Robust evidence exists to suggest that long-term benzodiazepine prescribing has serious repercussions for health, and that there is increased risk of mortality when co-prescribed with opioids.^[50] However, at present there is a lack of published research that explicitly compares the risks and outcomes associated with benzodiazepine prescribing in the treatment of substance dependency against those of street benzodiazepine use, particularly in a Scottish context.

Benzodiazepine prescribing is alternatively often advocated for within a harm reduction approach, acknowledging the crisis posed by the prevalence of street benzodiazepines.^[51] In 2020, the Drug Deaths Taskforce developed a set of principles and guidance for benzodiazepine prescribing, which offers direction for assessment, treatment planning and prescribing practice. The guidance acknowledges an inherent level of risk to the patient, which nonetheless may be comparatively lower than harms associated with street benzodiazepines.^[52] It further emphasises the importance of needs-based assessments tailored to the individual; the weighing and documentation of risks associated with both pharmacological intervention and use of street benzodiazepines; and that new benzodiazepine prescribing may stabilise street benzodiazepine use in the short-term.

Despite reductions in benzodiazepine prescriptions for the treatment of substance use disorders in Scotland since 2006, there has not been an equivalent fall in prescribable benzodiazepine-related deaths (which have remained stable) or sedative-related hospital stay rates (which have seen an increase). This must be viewed in the context of the proliferation of street benzodiazepines since the mid-2010's which have significantly increased the availability and affordability of these drugs over the same period. The EMCDDA does, however, highlight the potential relationship between reduced prescribing and the rising prevalence of new benzodiazepines, stating that 'the increase in new benzodiazepines might […] be partially related to well-intentioned restrictions in the legal supply of authorised benzodiazepine medicines and the introduction of prescription limits in order to prevent or reduce harms among patients, such as dependence.'^[53]

Further work is therefore required to determine quality prescribing practice and review the safety and efficacy of benzodiazepine prescribing as a treatment option for substance dependency, particularly if being co-prescribed with OST. In support of this aim, the Scottish Government is currently funding research through the Drug Deaths Taskforce Research Fund that explores the safety of benzodiazepine prescribing with OST.^[54] Researchers from the University of Stirling have undertaken a multicentre retrospective cohort study that aims to describe the prevalence, characteristics and patient outcomes associated with benzodiazepine prescribing among 1,350 people receiving OST in Scotland; work that is expected to inform future policy and practice.