I used Oxypowder and it is efficient... however I've come to see it as more of a "symptom fix" rather than a solution. I'm still figuring out these issus of constipaton myself, but for now I'm taking Schulze's Intestinal Formula #1. This is also something that can be taken for a long time, but in my logic there may be a difference. Oxypowder may be good to clean things out, by liquifying (oxygenating) everything (ew) but the IF#1 has herbs that I hope give some nutritional benefit and help long term action.
But I don't think this is all that can fix long time constipation. I've been cleansing casually for years now. My biggest single breakthrough was a parasite cleanse followed by a Liver Flush and a bowel cleanse. I saw about 1,000 liver flukes! Liver function, as I understand it, is part of what makes the bowels function and I had major liver parasites. That has helped, but I'm sure I still have old stuff in my bowels and am working still to clean it out. So my plan: continue bowel cleansing, and a liver cleanse is coming up, too. Another thing, there are anti-parasitic herbs in both the bowel and liver cleansers I'll be using so I hope that helps. I'll keep on with this until I've reached the legendary 3x/day natural (unassisted) BMs that I hear are possible and ideal.