I used it for 6 months last spring and it didn't seem to add flakes much if at all. Was also using Lee's regular minoxidil (30%pg) at the time. Think the pg level in 2% spironolactone is pretty low.
Not sure if the spironolactone did any good as I was beginning my minoxidil results at the time. Stopping the spironolactone didn't hurt none.