Kombucha is said to help with constipation. I also struggled with chronic constipation for years. I did three bowel cleanses, 2 with oxygen cleansers; I found out that psyllium based Bowel Cleanses are not for most people with chronic constipation.
then I did liver cleanses...
Black Strap Molasses and cayenne pepper powder both may help you some as well as things like chlorella.