On second thought, give the donuts after the procedure, never hurts to play it save.
Serious, is this your first colonoscopy
? Are they looking for something, or is it just routine screening?
I had one in 1984, when things were pretty crude, and the memory has prevented me from doing another one.
That guy had me laying on my back, which is totally wrong, and tried to shove this gardenhose up there. He must have enjoyed the view, and all my protesting didn't help.