Q: Is vomit considered najasah, and does it nullify wudu?
A: Yes. Vomit is considered an impurity/najasah. It is considered such when the regurgitated food or drink reaches the stomach regardless if it changes state or not. Vomiting a minor amount does not nullify wudu. A large amount does.
This answer was collected from HanbaliDisciples.com. The questions have been answered by Imam John Starling.