How can you stop throw up from coming?

I have found that not eating something that irritates your stomach is the best solution. Then, drink a glass of soda, preferably, 7-Up, that has been stirred with a metal spoon will generally help. Call a nurse or doctor, there are public health lines attached to many public hospitals for more information. There are any number of serious reasons why a person may throw up besides eating food that does not agree, for example, a spider bite might also be a problem.