I tried doing a liver cleanse sleeping on my back with my head propped up on a pillow. The next day I had terrible heartburn for the first half of the day and I didn't get out any stones. All the other times (7 times) I've laid on my right side and I have always gotten stones out with no side effects. Many of my stones are the size of large grapes and one was almost the size of a golf ball. I do wonder sometimes though if I should try laying on my stomach but I'm kind of afraid to change a good thing.