Intended for healthcare professionals

Rapid response to:


Association between concurrent use of prescription opioids and benzodiazepines and overdose: retrospective analysis

BMJ 2017; 356 doi: (Published 14 March 2017) Cite this as: BMJ 2017;356:j760

Rapid Response:

Distress is likely to cause both co-prescription and overdose and should be main focus of changes to care

Sun et al provide a helpful new finding on the increase in total and long term opioid prescribing in parts of the US, along with co-prescriptions of benzodiazepines and related increased risk of opiate overdose.

We suggest the assumptions about causation (which are not clear) underlying the calculations of how many overdoses could be reduced if practice were changed are too simple and are not justified.

Patient distress is likely to lead both to more benzodiazepine (and opioid) prescribing and directly to overdoses: A classic case of confounding. A clinical diagnosis of depression (among many other variables) was used to adjust the estimate, but because this was binary and the diagnosed prevalence of 17% is likely to be an underestimate for a population like this, much of the effect of mental distress is likely to remain unadjusted for.

So, if it is mental distress leading to both the benzodiazepine prescriptions and the overdoses, in at least some of the cases, eliminating benzodiazepine co-prescription with opioids is unlikely to reduce harm by the degree expected, or at all.

The clinical implications of this are that patients being prescribed opiates for whom distress is present or the co-prescription of psychotropic medications such as benzodiazepines is being considered, prescribers should think about underlying distress, definitive mental health problems, and risks. All problems identified should then be managed in accordance with the best evidence available.

Competing interests: No competing interests

20 March 2017
Richard Byng
GP and Professor in Primary Care Research
William Lee, Psychiatrist and Reader in Psychiatric Epidemiology
Plymouth University Peninsula Schools of Medicine and Dentistry
ITTC Building, Plymouth Science Park, PL6 8BX, UK