Inhaling something into your lung isn't going to cause intestinal cramping unless it's extremely toxic
What is toxic to one person may not be toxic to another, a good example is inhaling PG for people highly allergic to PG.
Or in my case, inhaling anything with cinnamon, which is toxic for me and which I found out "the hard way" about. (almost required an ER visit).
So when you say "toxic" that is a relative word here.
Incomplete inhalation, i..e, a spitting atty, which puts ejuice into your mouth instead of vaporizing into lungs, can certainly cause severe intestinal cramping and GERD. Does for me, and plenty of internet posts to support that others have this problem. But of course that is not really inhalation so you would be right about that.
Again, sorry, didn't mean to be snarky, I guess all this just goes toward showing the failings of trying to diagnose people's medical problems on an internet forum.
They should just go see a doctor, even though we are always trying to be helpful.