XYREM and off-label prescribing

[bcubed]

SWIM knows XYREM (pharmaceutical GHB) is indicated for relatively few disorders (narcolepsy and fibromyalgia, for example). SWIM also knows, however, that once a drug is liscenced, a physician has wide authority to prescribe off-label. From Wikipedia:

However, once the FDA approves a drug for prescription use, they do not attempt to regulate the practice of medicine, and so the physician makes decisions based on her or his best judgment.

However, I imagine there must be limits: I can't imagine a M.D. who prescribed phamacutical cocaine for obesity, for example, would have a lengthy career.

Another wiki quote:

Xyrem is distributed directly from the manufacturer and cannot be accessed by licensed pharmacists. It is therefore even more tightly controlled than most Schedule II drugs.

So suppose the following scenario: woman approaches her G.P. and says: "Doc, my husband and I would love to have a child, but I have been consistently unable to quit drinking after repeated attempts. I cannot ethically risk bringing a FAS child into this world. But if you could just give me something that closely mimics alcohol, I'm sure I avoid alcohol for the length of my pregnancy."

Doc considers and prescribes Xyrem off-label. What happens to doc?

Incidentally, I think I caught an error when wiki said XYREM/GHB was the ONLY case of one drug having two schedules: what about marijuana and marinol? (Though I suppose you could say marinol is THC and marijuana is a collection of psycoactive substances, if you wanted to nitpick.)