We have a significant number  of people with gastrointestinal autoimmune conditions like Crone's but I've never personally seen any of them vomit in my presence. I've never vomited around other Weres. It's pretty rare that I vomit at all. I guess around 17 years ago, something hit me and I lost my supper. I was over it the next day.

A few of us tend to over-extend ourselves. We metabolize alcohol pretty quickly but there is a brief brush with hangovers and such. Just stay away from them the morning after and let them get it out of their systems.