Is multi-level marketing illegal for a physician/PA/Nurse Practitioner to engage in with clients? My girlfriend went to a new nurse practitioner at her usual gynecologist's office who gave her packets of information and trial size herbs/vitamins, then she strongly recommended my girlfriend to purchase over 100$ worth of specific products. She had to carry it out inside of a trial prescription case and was told not to talk about it because the NP was unsure how the physician would feel about it. I looked into the company (Amazon Herb Co.) and it turns out it is a multi-level marketing business and this NP will get commission if my girlfriend were to purchase these products that the NP recommended. Furthermore, the NP talked about this stuff for 15+ minutes, never once mentioning that she has a financial interest in the sale of this stuff. How is this not illegal? Or at the very least in violation of professional standards?