Dulcolax
"I took this because I was having an ultrasound the next day and my doctor wanted me reasonably cleaned out.  I took 2 tabs at 8pm.  I woke at 4am with bad stomach cramps.  I moved into the bathroom for the next hour, where I experienced crippling stomach cramps, nausea and vomiting (mostly dry heaves as my stomach was fairly empty.  I actually thought about calling 911.  That bad!  I was burning up and sweating profusely - and I typically never sweat. It was the worst I've ever felt in my 56 years. The product worked.  Several hours later I'm still with some diarrhea, and the other symptoms are somewhat better, but I'm never, ever taking this poison again!"