Colonoscopy ~10 yrs out

I am scheduled for an upper GI and Colonoscopy tomorrow and am trying to do the bowel prep. The problem is I can not drink the 4 liters of prep solution. I've drank about 8 oz so far and am so full. How will I ever be able to finish this 4 liter bottle? 
This is my first colonoscopy, but my second Upper GI scope to search for an ulcer. After the last UGI, my doc said my stomach was at 2.5 centimeters, which is great for being 10 yrs out.  (RNY) But this is a real challenge to try to chug 4 liters of water, which they want you to do 8 oz every 10 min. I don't think it's gonna happen.
I did ask for a smaller/stronger method. You would think that would be a mandatory for bypass patients.
Anyone else have this issue, and how did you handle it?

Call now and ask if they can call you in the low volume prep.

They may cancel your procedure if you don't follow their instructions (and charge you a fee for the cancellation).

They may not have thought about your RNY ... If you are seeing a gastroenterologist for the colonoscopy, they probably give thesame protocol to everyone.  You should have insisted ona low volume prep.

It's too late now. I did request the low volume prep from the doctor, again from the office person who calls in the prescriptions, and a third time from the pharmacy. My husband went to pick it up and brought home this 4 liter jug.
It's ok... I'll just do the best I can. I think the time is less of an issue than actually getting the powdered contents down and staying hydrated. Ultimately I mixed it with less water and am on my 3rd 8oz glass. 
Thanks for the reply.

I did Moviprep - can't imagine having to do what you are doing - good luck!

I think most people so far out would be able to drink 8 oz in 10 minutes.  Since RNY patients don't have a pyloric valve between the pouch and small intestines, liquids usually go right through the pouch.  If you're unable to drink much at a time, I'd discuss it with your doc.