I hate this whole crap about "autism comes from the gut" or whatever. **I say this as a semi-verbal, "why's that adult flapping and wandering in Walmart?!" autistic person
Am I very sensitive to any discomfort in my stomach/intestines? Yes I am.
Does this sensitivity mean that sometimes I can become overstimulated by this discomfort, even with no other stressful input? Yes, sometimes.
Heck, a loud room and a pain in my "gut" is sometimes enough to make me sweaty and need to leave the room.
Not all autistic people experience this particular thing. But even if we did, we don't need endless supplements or enemas or ABA or spankings- we need compassion. Even if you can't understand us, understand that we aren't being difficult, the world is difficult for us!
If you are overwhelmed by your autistic child, an older autistic person may be able to offer insight.