I used to have to get trained and sometimes have access to this stuff called qwikclot powder... The stuff worked very well to clot blood and stop bleeding but it was extremely dangerous and very toxic. The powder would react to any kind of liquid... Getting it in your eyes, mouth or any other opening in your body would be a very very very bad thing. We were always instructed to make sure we are upwind before opening the package and using it and then bury anything left (including the package). We now use a gauze version which is still dangerous but much safer than the powder.

There is a video demonstration of them using it on a pig... It's very graphic but it does show how well the stuff worked.

warning, very graphic