This is a real thing, the screaming vomits, or “scromits” are a potential side effect of smoking marijuana. According to a source (see below) it is the result of long term high does use of cannabis and can last for weeks.
The word “scromit” was invented in 2008, but the phenomenon was noted in research in 2004. Apparently, this has become a lot more common.
However, cannabis proponents say this is a very rare condition and the threat is overblown.
I was not able to find a video of anyone actively in the throes of scromiting, apparently it is mostly done in private.