The first two times I used it, it didn't seem to be that effective and it gave me painful cramps both times. But the last two times I used it, it worked without pain. I've been inactive for a week because I've been sick. My doctor had recommended Mirolax. I had done that for two days with Gatorade without results. Then took the Prunex and got results in a few hours. I don't know if Mirolax had anything to do with it or not. Anyway, the package says to take it before bed. I got better results when I took it in the morning. Even though by itself, it may or may not be as effective as it was this time, I still plan to order it as a back up. I have two other friends who use it regularly.