Polyethylene glycol 3350
"I was so constipated I did not have  a bowel movement for 6 days. Tried Senna, Exlax. I just could not go so i mixed a small bottle of Miralax in 2 x 16oz bottles of prune juice i drank the 2 bottles and wow total explosion within 20 min. I did not expect that to work that fast. "