Bisacodyl
"Very effective in stimulating a BM. However, this medicine can cause bad stomach cramps, bloating and nausea. I'm used to this as I have had constipation my whole life so take laxatives a lot. However, I would only take this if more natural methods of relieving constipation aren't working. Definitely do not take this medicine if you are out or working the next day! you won't feel well."