I think the best thing to do would be to call the doctor's office tomorrow and explain your nervousness about the ducolax and the cramps it gave you in the past - maybe they have an alternative they could have you do.
As far as the prep still being actice when you go in for your appointment, you could ask about that, also. My experience has been that the doctor's instructions are 'spot on", timing-wise, and I've not had an issue.
I used to have to travel 1 1/2 hours for my scopings, and when I had an 8 am appointment, I'd have to get up at 3 to take the second dose (when the prep required two doses)....At my pre-scoping appointment, they would sit there with me and count out the hours and figure it out so I'd be ok for the trip. So, probably what your doc's office has you doing is fine, but really, I'd call and ask!
Keep us posted!
Co-Moderator, UC Forum
Age 54. Diagnosed UP 1983, UC 1986
Prednisone almost 2 years, 86-88
Asacol - 16 pills/day, cortenemas, Rowasa
Metamucil - 2 doses/day since '86
VSL#3DS, Multivitamin, Calcium and D
homemade yogurt each day
hip replacement 4/5/10
Son, 16, dx pancolitis 2007