Sprinkle just a hint of Bentonite in the water and food. I'd make sure the food was watered down a bit to a mush consistancy so that she would not get dehydrated.
I'd give her acidophilus - 1/4 tsp as a treat a few hours before feeding her.
keep an eye to make sure she is eliminating properly.
An enema may be considered - possibly a week or two later.
If you're going to give vitamin C, make sure it's sodium ascorbate. It won't irritate the stomach.