My sister thinks that her oldest cat, Matilda, may have one. Our vets is closed for the weekend and we have no Emergency Pet Clinic near us, is there anyway to tell. She said that Matilda threw up a little bit of blood.
Does her vet have an emergeny number she can reach her at? Is there a teaching vet hospital nearby? She should be seen ASAP if she is throwing up some blood and getting her in to a vet is very important even if you have to travel a small distance.
My RB cat had an bleeding ulcer among his other health issues. We were scared when he puked up some blood as well. We took him in to our local vet the same day and did tests to see what it was. He was prescribed a prescription for it (Can't remember the name) and he was fine afterwards. (as long as we were observant) It did flare up a couple of times.
Hopefully your sister can get her in soon and have them run tests to eliminate any other causes. Please keep us poted on what you find out.