Why do you feel nauseas but cough heavily before vomiting?

Answer 1

I feel nauseas a bit and i feel like i am just about to throw up in the toilet so i am sitting next to the toilet with the toilet seat lid up i cough heavily before i start vomiting because when i do the big heavy cough it like coughs up the vomit and the flem so before i vomit i do another big cough to get the flem and the vomit up Thanks Harriet