I put one of these Chinese cups on the upper part of my chest, the night before last, and after several minutes it started to fill up with blood. I took it off right away. It kind of freaked me out, but it stopped bleeding as soon as I pulled it off. All I can figure is there must've been a small scab, or a mole, or something there. I really couldn't tell where the blood came from. It was just kind of weird.

I've actually seen youtube videos, where they will make a small cut on the skin before applying the cup, to draw toxins and poisons out of an area, so I guess it doesn't cause any harm. It's just kind of nasty to see a cup full of blood. I've been using these cups a lot and that's the only time it's happened.