Hi, quck response, since I am at work:
I use chanca piedra every day, dried leaves as a tea, very bitter, yech!!
Helps with my period and do not know if it helps with the flush. Done 4 so far and all yielded numerous little green soft stones. I do not see big tan ones, but that can be due to my toilet, being a "plumpsklo".

I bought my chanca piedra tea at http://www.tropilab.com. Very good quiality, veru good service, very good price.
They also have tinctures.