If I get a bloody nose, please don't put a tampon in it.
I would prefer just to spit the blood out of my mouth if my mouth is bleeding.
Now, if I am halfway up a route, and a severe attack of diarrhea were to occur, a tampon would sure be a great thing to have. From now on, instead of fouling myself and the route I am on, I will always keep a tampon at the ready. Perhaps taped to the rim of my helmet.