Q. We have a cat that is throwing up randomly 3 times. What's wrong?
A. It could be many things. What time period is it over, days or just an hour? What is it bringing up? Food? Water? Worms? Bile?. Has the cat had access to anything toxic? Has the cat got any other symptoms?
If it has had access to anything toxic then contact your vet immediately. If it is otherwise fine in itself and is just vomiting food you could try starving it for 12 hours to start with, still allow it access to water. If it still vomits or has any other symptoms then contact your local vet.