JoAnn,
I don't have a Loop Ileo, but I have had several feet of my small intestine removed due to CD (as well as all of the large and the rectum). So I can speak a bit about the dehydration issues. Sorry I can't help a lot with the other questions tho.
I have taken up to 9 immodium a day - 3 with each main meal. BUT I am now down to only 3 a day - first thing in the morning. That seems to be my busiest time! Anyway, here are some of the alterations I have made to my diet in the last couple of years that has seemed to really help slow my output.
First off, I don't drink caffeine. No regular coffee, but I do drink a large, homemade decaf latte in the mornings, along with a fuit grain bar and a banana.
I no longer drink carbonated sodas... I switched to Cranberry/Black Cherry Juice or Cranberry/Peach juice cut with 2/3 water and 1/3 juice. I mixe them in my water bottles. That means I get about 8 water bottles per gallon of juice. I still get some of the sugar, but none of the carbonation. I got tired of gatorade and this is working for me for now.
I also have really tightened up on the amount of spicy foods and fried foods I eat.
I tend to eat lots of rice and baked potatoes. Also applesauce works well. I don't totally concentrate on what my diet is, but it is a way of life. I can eat about anything, except some of the more fibery foods. I'm more fearful of blockages than anything - I've had several partial blockages in my past.
I hope this addresses some of the output issues. Oh yea, they say increasing your sodium, ie pretzels, crackers, etc, will also help the dehydration issues. I tend to automatically eat more salty stuff anyway.
Good luck JoAnn.