Well, she can try some of the over the counter remedies, but to be honest I found that I needed to get something prescribed by the doctor to get some real relief (I have a peptic ulcer and Crohn's Disease). Didn't the doctor give her something for the pain when he diagnosed her? If not, then get an urgent request for a gastroenterologist (sp?) if you are dealing with your family doctor or go back to your family doctor if you're dealing with a specialist.
She shouldn't take anything the day of the scope (they need to see the interior lining and most things that help would be coating it), but there is no reason she can't get something while she's waiting.
Until then try Pepto-Bismol and reducing her diet (have her just eat plain rice, then if that sits well add in something else that is very plain and so on) to avoid stressing her system that way. Make sure she eats something though, as not eating will just make her system more acidic and aggravate everything. Even if it is just a handful of soda crackers, eat 3-4 times per day minimum (I basically had to do this for two months - eating a few scoops of white rice or a handful of crackers every 3-4 hours - when the Crohn's got really bad). Avoid coffee, soda, acidic juices, spicy foods, and anything else that bothers her.
Good luck!