And that's why I somewhat revised and clarified by original statement by saying that Disneyland may not be the best place to start with. Better to begin with a safer environment, one where it's plenty possible to have the sensations but quite difficult to hurt oneself. But from the sound of it, the OP's brother doesn't suffer from anxiety related to the rides. In all likelihood, any panic attacks that occurred would be in the middle of crowded walkways, not on the rides. Those are unpleasant places for anyone, but they only become dangerous when you've got a lot of people moving enthusiastically in the same direction (e.g. after the fireworks). And those are generally good to avoid no matter whether or not one has anxiety issues.Panic disorder can have physical symptoms involving a person's perception and coordination. Add to it the moving rides that the person may be on at Disneyland, and the possibility that the person may be on meds, and yes, it could be physically threatening to himself and to others.