During my time doing MES pharm P2Ps I got quite experienced at this. It's a very uncomfortable topic to address with another doc. It's easy to assume they know what they're doing and are just too weak to say no to the patient, which may well be true. I had the most success when bringing up the lack of documented success they've had with the patient and trying to empathize with their difficulty controlling the patient's pain. Once they begin to open up, then you can start to ask questions about how the opiates got onboard, the escalation, any attempts to get the patient to cut back, etc. It's not fun at all, but in the end if you're successful it's rewarding. Most docs I spoke with who do this are just looking for some help. Some would even take my information for future curbside consults!
My biggest challenge were the guys who adamantly defended what they were doing. There was one guy who would cite all kinds of data and recite pharmacological mechanisms to defend practices like using outrageously expensive and inappropriate fentora for "breakthrough" pain in a CLBP patient. Very smart guy, but totally wrongheaded (or in the pocket of the fentora rep).
