I used Parastroy a couple months ago. I did notice some die off (or side effects) from it. I was pretty lethargic and sluggish. I always looked at my stools to see if I had passed any parasites, worms, etc., but I did not see anything. I guess I either didn't have any, or I did, but they were just too small for me to see. Not to be gross, but I did not "handle" my stools physically-just looked at them. So, if there were some parasites, they were probably deeper inside my stools than I was willing to look! LOL
FYI-I got my Parastroy at Amazon.com. I can't remember how much I paid for it though. You might want to compare their price with iherb's.