Bisacodyl is a stimulant laxative that triggers bowel movements. It pulls out the water and fluids from the stomach and intestine, thereby excreting it. You may experience a slight change in your weight as water is pulled out of your body, but it does not aid weight loss. Bisacodyl is not recommended as a long-term medication, so even if you lose some pounds while taking Bisacodyl, you will gain it back soon.