Dec 05, 2018: Researchers found 24,000 chronic opioid users were prescribed either a central nervous system depressant, such as barbiturates or benzodiazepines. Concurrent use of opioids and benzodiazepines has been associated with a fivefold increase in the risk of overdose during the first 90 days of treatment.

Outside link:
A lot of times pharmacists are the ones who can really catch some of these things and facilitate communication