Quoting Glo♥:" She can quit without taking pills. Weed isn't addictive."
Not physically addictive like heroin, but a lot of people do form addictions in their head with pot. I know quite a few that start getting very anxious/angry/upset when they have to go without.
Do you know which pill he wants to put her on?
Wellbutrin is an anxiety/depression (I don't remember which) medication that has the same active ingredients as Zyban (which is for quitting cigarettes). I could see a Dr prescribing that, as there's always a possibility it may help.
I was put on Wellbutrin in high school to quit cigarettes (insurance company wouldn't cover zyban for a 17 y/o, Dr said Wellbutrin is basically the same thing) but I had a really bad allergic reaction to it.