"I do not regard vomiting as a danger signal, but as a cleansing process".
"As vomiting is merely part of the elimination that fasting encourages, most often due to over-activity of the liver with regurgitation of bile into the stomach, it needs only to be let alone. It may develop early or late in the fast, but it constitutes no danger, so far as my own experience and observations go".
Nature will take its course.
Problems and even fatalities are caused by the efforts in measure to stop the vomiting.