Propofol
"I had my first routine colonoscopy at 54. I am extremely sensitive to drugs of any kind. I did not feel a thing from the time the needles entered my arm. Found myself conscious of being a very dark, completely peaceful place. I was aware of that. I thought I was finally THERE and when the nurse started trying to rouse me, I was not coming back. Not happy to be bothered and so certain I didn't want to come back, I became aggressive to the nurse and as has happened before, began to cry hysterically. There were staff around me but I couldn't see them. My friend later told me they did not know what to do and had not seen this reaction before. So I was in recover quite a while, unable to come out of it."