In a paper co-authored by the famous Canadian pharmacologist David Juurlink, the plausible causal link between between opioid use and depression has been highlighted. It is argued that evidence suggests that depression (commonly observed amongst people with chronic pain) may in some cases represent an adverse effect of opioids. The review, published in the journal Pain, is compelling reading. Dr Jurlink previously wrote a pointed critique of the famous previously published letter to the editor of the New England Journal, which was entitled Addiction Rare in Patients Treated with Narcotics – as it turns out, a monumental mistake which in some circles is said to have contributed to the evolution of the current opioid epidemic.