Hospital pharmacy sees this for behavioral health patients. I’ve seen two used before but don’t recall three. Usually see SSRI + bupropion or ssri + venlafaxine, or SSRI + TCA but on occasion two SSRI’s. The cocktails that the psych doctors use sometimes can be weird but their is often evidence or they have to try something that looks weird but works for the individual patient. Progress notes and relatively easy access to the doctors make it more convenient to research and confirm.

For retail, I would make sure that the prescriber specializes in mental health or behavioral medicine, is the one prescribing all three, and request and explanation/diagnosis.