Flaxseed is not only a bowel cleanse, not only antifungal but also a prebiotic which helps friendly bacteria make a home into your bowels.
It is highly efficient because, like psyllium, it adheres to the intestinal walls. Hence the delayed reaction, since the flax accumulates over time and remain there it decuplates its quantity and effect. Furthermore, by adering to the intestinal wall it can better evict candida and welcome friendly bacteria.
Heavy die off is something you want to avoid. It means your metabolsim no longer copes and healthy cells are damaged in the process. At this point, I only take flax every second day or else I get too much die-off and pain in my colon. I find that flax and kefir to be a marvelous combo.
Here is the standard flax Bowel Cleanse recipe://www.curezone.org/blogs/fm.asp?i=976144
Many people who cannot handle psyllium like this cleanse.